One of the good things about a G-Shock fan is that there are so darn many models out there. And they're updated frequently, so if you don't see what you want, it'll be there sooner than you think. We've reviewed quite a few G-Shocks, and think that they represent excellent value and function. Today's review is of the AWG101-1V, an analog-digital watch very similar to the GW-1310. Compared to the 1310, this one uses a red hour hand and reverse LCD displays (black on white) but is otherwise of similar style. As with all G-Shocks, you get a tremendous amount of functionality:

View the Casio G-Shock Gulfman GW-9100 photo gallery.

The new Casio G-Shock Gulfman is an interesting new addition to Casio's G-Shock line. It has the same set of features as all the G-Shocks I review:

• Atomic calibration.
• Solar powered.
• 200 meter water resistant (about 650 feet).
• Automatic calendar.
• Electroluminescent backlight.
• 48-city world time.
• 5 daily alarms, 1 snooze.
• 60 minute countdown timer.
• Stopwatch.

However, it also has a couple of new tricks:

• Multi-band atomic. That means it can calibrate in the US, UK, Germany, and Japan (most previous G-Shock models only calibrate in the US and Japan).
• Titanium case and caseback. Most G-Shocks use stainless steel, so the GW-9100 is slightly lighter, and slightly more corrosion resistant.

I like the new features of the GW-9100, and I also just really like the look. I like the texture of the titanium case, and the nice large LCD. It also has extra large buttons which makes it easier to operate than most G-Shocks.

If you're already happy with your solar atomic G-Shock, I don't think the new Gulfman represents such a big improvement that you need to rush out and buy it right away. But if you're thinking of getting into the G-Shock game, the GW-9100 is a very good place to start. It certainly makes a fine addition to my G-Shock collection.

View the Casio G-Shock Gulfman GW-9100 photo gallery.

Casio seems to be gradually bringing the G-Shock and Pathfinder lines closer together. The first Casio Riseman was introduced back in 1997, but has been discontinued for some time. About three years ago, Casio introduced the G-Shock GW-400J which borrows from the Pathfinder line by integrating a thermometer. More recently, Casio announced the Ultimate Pathfinder (PAW1500) which, like the G-Shock line, is now water resistant to 200 meters (650 feet) rather than the previous 100 meters. And now Casio is reviving the Riseman line with the very strong Casio Riseman GW-9200.

Features include:

• New multi-band atomic timekeeping. Most of Casio's atomic watches are multi-band now, meaning they calibrate with atomic clocks in Mainflingen (Germany), Rugby (England), Fort Collins (Colorado), Fukushima (Japan), and Fukuoka (also Japan). But the Riseman GW-9200 goes a step further by also calibrating with the 77.5 kHz atomic signal in China, making it the first 6-band atomic watch I've ever seen.
• Solar powered.
• Water-resistant to 200 meters, or about 650 feet.
• Barometer pressure indicator and differential pointer (graph) with a range of 260 to 1,100 hectoPascals (millibars).
• Altimeter with a range of -700 to 10,000 meters, altitude data storage, and altitude differential pointer (ascent/descent graph).
• Thermometer with a range of -10°C to 60°C.
• Stopwatch with a resolution of 1/100th of a second, and a maximum capacity of 24 hours.
• World time with support for 33 cities.
• Countdown timer with a maximum of 24 hours (a nice improvement over the Pathfinders).
• 5 daily alarms and one snooze alarm.
• Time transfer function which allows you to swap the primary time zone with a secondary time zone (simplifying frequent travel between two zones).
• Electroluminescent backlight with automatic illumination feature (the ability to automatically illuminate the LCD by tilting the watch toward you).
• Dimensions: 51mm x 48.8mm x 15.9mm, and 60.9g.

All that is keeping the new Riseman from being a true triple sensor Pathfinder is the digital compass which, unfortunately, is one of my favorite features of the Pathfinder line. However, the GW-9200 is clearly one of the most sophisticated digital watches on the planet. It looks fantastic, and has some additional small improvements like the ability to view the date and day of week simultaneously. I just hope that, unlike the GW-400J, we will be able to toggle between metric and imperial units for things like temperature and barometric pressure, however I'm guessing not, and I'm guessing it will not be released in the US (though I will be very happy to be proven wrong).

The Casio G-Shock Riseman GW-9200 will be available on June 28th, 2008 and will retail for ¥27,000 which, as of today, is about $260.

View the Casio G-Shock GW056A Photo Gallery.

I think of the Casio G-Shock GW056A as the G-Shock for people who don't like G-Shocks. It's certainly the most subtle and unrecognizable G-Shock currently in the lineup, and most importantly, the slimmest.

It has the same octagonal case as many of the older G-Shocks (and the new retro tribute G-Shocks), but the brushed stainless steel bezel makes the shape much more pronounced. In fact, the shape is the first thing you notice about the GW056A. My wife calls it my Battlestar Galactica watch because the unconventional shape is similar to the shape paper will apparently assume if the world is ever destroyed by Cylons (of course, I'm talking about the new Battlestar Galactica).

The extremely slim and lightweight design is really what sets the GW056A apart. In terms of features, you'll notice that it's on par with all my favorite G-Shocks:

• Atomic calibration (US and Japan).
• Solar powered.
• Shock resistant (naturally).
• Water resistant to 200 meters, or about 650 feet.
• Automatic calendar.
• Electroluminescent backlight with auto EL function (meaning it can automatically illuminate when tilted to about 40° in the dark).
• World time (48 cities, 29 time zones, and automatic daylight savings adjustment).
• Four daily alarms and one snooze alarm (which keeps sounding until explicitly disabled).
• Countdown timer (up to 60 minutes).
• Stopwatch with split time (resolution of 1/100th of a second, and a maximum time of 59:59.99).

I've owned my GW056A since they were first introduced in Japan about two years ago (which means mine is actually a GW056J — the identical Japanese version), and it still gets regular wrist time. I like to wear it in the winter because it fits nicely under my coat sleeve, and when I ride my motorcycle since it slips easily beneath a glove. Although I love each and every one of my Casios, sometimes its nice having all the G-Shock functionality without all the G-Shock bulk.

View the Casio G-Shock GW056A Photo Gallery.

View the Casio Giez 1000BJ Photo Gallery.

We first mentioned the Casio Giez 1000BJ almost a year ago, but we didn't have much to say other than its very cool looking, it's only available in Japan, and its insides are almost identical to the Oceanus 5 Motor (OCW600TDA-1AV). Now that I actually own one, however, I can finally give you a proper review.

The biggest difference in functionality between the Oceanus and the Casio G-Shock Giez is the fact that the Giez is not a worldwide atomic watch. In other words, the Giez 1000BJ only receives atomic time signals in Japan and the US — not in the UK and Germany like the Oceanus.

There are a few more obvious differences, as well. The style of the Giez is pure G-Shock with ion-plated black metal clad in durable black rubber. It's a very functional looking watch, and with the white hands over the black face, it's quite legible, as well. Casio muted the usual G-Shock promotion with the bezel lettering simply inset rather than painted; the result is a much more restrained look than your average G-shock.

Personally, I'm a big fan of tough analog watches, and I was really looking forward to this one. Not only does it have the legendary toughness of the Casio G-Shock family, but it's solar, atomic, and it even manages to pack in five motors. Shock-proofing motors is a lot harder than it sounds, and this watch represents an impressive technical achievement for Casio.

It looks like Casio just repackaged the Oceanus 5 Motor's insides in a dark and bold G-Shock GIEZ case. Currently only available to the Japanese (and to resourceful and fanatical foreign watch geeks), the Casio G-Shock GIEZ 1000BJ appears to be identical to the Oceanus 5 Motor that I just reviewed, but with a much tougher, "special ops" look to it.

Rather than titanium, the case is stainless steel with some sort of black, abrasion-resistant coating, and in place of the titanium bracelet is a pretty standard G-Shock rubber strap. The sapphire crystal of the Oceanus 5 Motor has also been replaced with whatever type of scratch-resistant plastic or acrylic that is used in G-Shocks. I'm not going to bother listing this watch's features since the Oceanus 5 Motor review covers them in detail (including a video), but I will say that aesthetically, this reinterpretation of the Oceanus really creates an entirely new watch.

In fact, there might even be some advantage in owning both since your titanium, around-the-office, out-for-drinks timepiece could work identically to your weekend, change-the-oil, help-a-friend-move "beater". I think there could be a marketing opportunity here.

The Casio G-Shock GIEZ 1000BJ goes for about $227.

Update: Read the Casio Giez 1000BJ review.

Over a year ago, I came across the Casio G-Shock GW400-J vibrating watch, and was so enraptured by the prospect of having an atomic solar G-Shock with a vibrating alarm that I ordered one immediately. Unfortunately, they were only available in Japan, so I had to buy it "gray market" and pay top dollar. I reviewed the GW400J as soon as I received it, and the story got so much traffic that I got an email from Casio asking me to make it very clear in the article that the watch was only available in Japan because they were getting so many calls from people in the US trying to buy one. Of course I agreed to make the change, but I also used the opportunity to encourage Casio to try releasing the GW400J (and other cool new G-Shocks) to us poor Yanks who I believe are starting to love geeky wrist gadgets as much as the Japanese. I never heard back directly, but while doing a routine scrub of Casio's online watch selection the other day, I was pleased to find the G-Shock GW400J-1 available for sale on the US site.

I gave Casio a call, and was told that the only difference between the GW400J (the Japanese version) and the GW400J-1 (the US version) is that the temperature (yes, the watch has a thermometer, as well) on the US version can be displayed in both fahrenheit and in celsius whereas the Japanese version only supports celsius. Keep in mind that I have not confirmed this for myself, so if you buy one, and you absolutely need the temperature to be in fahrenheit, save your receipt.

So now I'm faced with a difficult decision. Do I spend $200 replacing my GW400J with a GW400J-1 just to get the temperature in fahrenheit, or do I stick with my gray market Japanese version? I'll probably save my $200 for whatever vibrating solar atomic contraption Casio releases next, however if I happen to come face to face with one in a store, I reserve the right to change my mind and buy it on the spot.

I'm obviously a big fan of the GW400J-1. I would definitely say that it's one of the top five most interesting G-Shocks out there. For a thorough rundown, check out my review of the GW400J. Or better yet, pick one up yourself and get to know it firsthand.

Update and Warning: I've received a few emails from people who have purchased the GW400 in the US, and they have not been able to figure out how to change the temperature units over to fahrenheit. It's possible Casio did not modify the watch before releasing it in the US. Shame on them.

I love the idea of vibrating alarms. I think a vibrating alarm on a watch makes as much sense as a vibrating ringer on a mobile phone. Unfortunately, if you want a silent watch, you don't have a lot of choices. Some options that come to mind are the Tissot High-T, the Tissot Silen-T, the Casio G-Shock GW-400J, and now the newest addition: the Casio G-Shock GL-7500HD.

The Casio GL-7500HD is a watch intended for water sports, the idea being if your swimming, surfing, water skiing, etc., you're not likely to hear an alarm. Additional water-related features include a tide graph and water resistance to 200 meters (about 650 feet).  Here's the full feature list for the Casio GL-7500HD:

• Vibrating alarm.
• Tide graph.
• World time (preprogrammed for 28 cities).
• Three daily alarms and one snooze alarm.
• Countdown timer.
• Stopwatch with a resolution of 1/100 of a second.
• Automatic calendar.
• Water-resistant to 200 meters, or about 650 feet.

As far as my own personal G-Shock collection goes, I usually don't bother with anything that isn't atomic and solar anymore simply because I think those are two very useful features that Casio has really implemented well (see the Casio G-Shock GW-400J). But if your criteria is less stringent, and your priorities are a tough, inexpensive watch with a vibrating alarm, The Casio G-Shock GL-7500HD looks like a very good fit. And it is readily available in the US for only around $80.

I just got back from a trip to Seoul and Hong Kong where I did quite a bit of watch shopping. I've spent a lot of time in Japan, and I learned very quickly that both fine and high-tech watches are a much bigger priority in many parts of Asia than they are in the US, so finding jewelry stores and watchmakers was not difficult, especially in Hong Kong.

I picked up the two watches pictured here as gifts. The one on the right is a Casio G-Shock GW-1100J which is very similar to one I reviewed almost a year ago. The only differences are the colors of the LCDs, and the red accents on the newer one. This is a great, feature rich watch (atomic, solar, countdown timer, five alarms, world time, automatic backlight, etc.), and has a bold, tough look. I got it at a G-Shock store that happened to be right across the street from my hotel in Hong Kong. Their selection actually wasn't as extensive as I'd hoped. In fact, there are several new Casios available in Japan that they didn't cary yet or even know anything about. Their atomic selection was a little sparse, as well, most likely because there is no atomic clock within range (the nearest two are both in Japan). Clearly the best place in the world to shop for Casios is at their source: Tokyo.

The other watch I picked up is the Seiko Sportura SNA481. I've written pretty extensively about the Sportura line, and recently reviewed the SNJ005 World Time. These are neither pricey nor rare watches, but they are very well made, and have a distinctive, sporty look -- especially the line with the black leather straps, in my opinion. The SNA481 is the alarm chronograph. The chronograph uses the large orange hand to track seconds, and the subdial at the 12 o'clock position to track up to 60 minutes. The subdial at the six o'clock position is used for setting the alarm, or for tracking the time in a second time zone.

I've determined that the king of watches in Asia is not a Japanese brand, however. Clearly it's Rolex. Walking through the shopping districts of Hong Kong at night, you see the word "Rolex" in neon all over the place, and everyone who can possibly scrape enough money together seems to have one. There are no bargains to be had on Rolexes in Hong Kong, however. I came across a very rare white dial, all stainless Rolex Daytona for well over $10,000 (US), which I believe retails for thousands less here. The problem, however, is finding one stateside. The only one I've ever seen in the US was a 1998 model with a Zenith movement in a pricey shopping district in San Francisco for $14,000. Price-wise, it makes my GMT Master II look like a Timex.

When I arrived home yesterday, I was pleased to find several packages from all over the world waiting for me. Watch for reviews in the coming weeks.

View the Casio G-Shock GW-5600 photo gallery.

The GW-5600 is a remake of the very first Casio G-Shock: the 1983 DW-5000C. I fell in love with the GW-5600 series the first time I saw it both for its boxy, retro styling, and for its plain but essential feature set. In fact, the GW-5600 has the exact set of features that I believe makes up a complete and functional modern digital watch:

• Atomic time keeping. Calibrates in both Japan and in the US.
• Solar powered. With the power-saving function enabled, the watch will remain powered for up to 25 months with no light.
• Countdown timer with a maximum time of 60 minutes, and a resolution of 1/10th of a second.
• 4 standard daily alarms, 1 daily snooze alarm, and an hourly time signal.
• Stopwatch with a resolution of 1/100th of a second, and split time.
• World time for 30 different cities (29 time zones).
• Automatic calendar.
• Water resistant to 20 bar, 200 meters, or 660 feet.
• Battery power indicator.
• Signal reception indicator.
• Electroluminescent backlight.

The GW-5600 is available in a few different models. I chose the one with the inverted LCD (the GW-5600BJ) simply to have something a little different, however the contrast isn't as high in real life as Casio's depictions would have you believe, which means it's a little difficult to read (I would probably recommend going with the standard LCD of the GW-5600J). Other than that, the GW-5600 is a simple but functional digital watch which manages to be both retro and modern.

• Casio G-Shock GW-5600 photo gallery.
• The Casio G-Shock GW-5600 product line.
• Casio G-Shock timeline.

View the Casio G-Shock GW-400J photo gallery.

When I first saw the new Casio GW-400J vibrating watch, I knew I was going to have to get my hands on one. You see, I'm very in to vibrating watches. Not because I'm some kind horological pervert, but because they make so much sense. Ever since a got my Timex Internet Messenger some six years ago or so, I've always felt that digital watches should have vibrating alarms. What good is it having multiple daily alarms, programmable alarms, auto-repeating countdown timers, and an hourly signal if you can't hear them because they are so faint, or because you live in a world where you don't want your geeky watch attracting attention?

Not only was I tempted by the Casio GW-400J's vibrating alarm, but it's even solar powered. And atomic. And it has a countdown timer. True, it's goofy looking, but I just named all my favorite digital watch features, and it's very unusual to find them all in one place. Besides, big black plastic Casios appear to be in right now, at least in San Francisco where I live.

Before I get into my review of the Casio GW-400J, here's a list of features:

I'm only doing a mini review of the Casio G-Shock GW-1310 because it is almost identical to the G-Shock GW-1100 that I reviewed late last year with just a few subtle differences. Before reading what's different between the two watches, you should probably check out that review first, if you haven't already. Here's a quick recap of the features the two watches have in common:

• Solar powered.
• Atomic timekeeping.
• World time.
• Five daily alarms.
• Auto-repeating countdown timer.
• Stopwatch.
• Water resistant to 200 meters, or 600 feet.
• Shock resistant.
• Scratch-resistant mineral crystal.

(Check out the GW-1100 review for a much more detail description of these features.)

The GW-1310 is a newer watch, and has been updated in the following ways:

The folks over at Wrist Dreams have picked up on the new vibrating Casio G-Shock GW-400CJ-1JF marine sports watch. I was just commenting the other day on how Casio is really pushing the limits of digital watches, and as if to prove my point, they announce one of the most interesting and feature-rich digital watches I've ever seen. The most unique feature of the GW-400CJ is that the countdown timer, alarm, and time signal can use a vibrating alarm rather than an audible one so that it can be effectively used in high winds, while in the water, or in other situations where it's difficult to hear faint high-pitched beeps. The other thing that really caught my attention about this watch is the sheer number of features they packed into it:

• Waveceptor. That means this watch is automatically calibrated through radio waves transmitted by atomic clocks. Works in both Japan and the US.
• Tough Solar. Solar cells around the face keep the watch's battery charged, and a sophisticated power-saving function will keep the watch powered for up to 19 months with no light.
• Water-resistant to 200 meters, or over 600 feet, which makes it suitable for diving.
• Thermometer which measures both air and water temperatures between about 14 to 140 degrees Fahrenheit.
• Tide graph.
• Moon phase indicator.
• Vibrating alarm.
• World time supporting 32 cities in 30 time zones.
• Stopwatch with a resolution of 1/100th of a second and a max time of 100 hours.
• Four alarms.
• Countdown timer. Goes up to 60 minutes and has an auto-repeat function.
• Automatic calendar.
• Electroluminescent backlight.

A truly amazing watch. Read the press release in English, thanks to Google's translation tool. The Casio GW-400CJ should go for around $225, not counting shipping from Japan, and a generous tip for your Japanese connection.

I'll admit that Watch Report tends to be a little biased toward men's watches, but being a pretty big G-Shock fan in general, I have to make the occasional exception for Baby-G's. If you're a guy, and you're about to head off to Google to search for a more manly watch, aren't you forgetting that it's almost the holidays, and that Casio Baby-G watches make wonderful and affordable gifts?

As far as I know, these are the first G-Shocks (Baby or otherwise) to appear as anything other than round (or roundish) since the initial square G-Shocks were introduced back in 1983. They rounded out in 1987, and have remained that way until now. Not only are these newest Baby-G's square, but they're colorful, sophisticated, and fun. In the words of David Johnson, vice president of Casio's Timepiece Division:

"Casio's newest timepieces are trendy, stylish and extremely functional. The Baby-G's are the perfect accessory for today's busy lifestyle, matching
supreme style with advanced features that make your life easier. The new square Baby-G's are just the right thing to add a dash of rogue style to the latest spring looks. On the flip side they can add the necessary polish to an outfit for the boardroom. As versatile as they are chic, they're a sign of the times. It's hip to be square!"

While I'm pretty sure these words were actually written by someone in PR and/or Marketing as opposed to being uttered by David Johnson himself, I wouldn't disagree with them. Now let's have a look at features.

View the Casio GW-1100 photo gallery.

I reviewed this watch's all-digital little brother about a month ago, and found it to be a good watch for someone who needs something durable and inexpensive. If you're really into Casio G-Shocks, though, you'll definitely want to look at something more like the GW-1100 and its peers.

This is a big, bold G-Shock that's just about as feature-rich as they come. It's not exactly a lightweight, inconspicuous timepiece, but people don't wear G-Shocks when they want their wrists to go unnoticed. Despite its size, weight, height, and the fact that there are ten noticeable screws keeping this watch water and dust-tight, I think it actually manages to convey a touch more class than your typical G-Shock.

Features of the GW-1100

• Solar powered. The face of the watch, behind the hands and in front of the four LCDs, is a good-sized solar cell which easily keeps this watch's battery well charged. A couple of minutes of direct sunlight each day is the best way to keep a Tough Solar G-Shock happy (normal incandescent, and even fluorescent, lighting can also be used, though you'll need substantially more of it), however Casio claims that a fully charged battery will power this model through normal use for up to seven months. I don't have time to sit in the dark for seven months to test this theory, but I will say that even after prolonged disuse (so many watches, so little time), whenever I pick it back up, the battery has always been nearly fully charged, so my guess is that Casio's claims are accurate. You don't want to let the battery completely discharge, though, since it takes 24 hours of direct sunlight to fully recharge it which is not an easy feat unless you happen to be orbiting the Earth.
• Battery charge indicator. The LCD at the 6 o'clock position will let you know when you've been cooped up in your dark basement for too long, and that it's time to get out into the sunshine for a little recharging.
• Power saving function. When not exposed to light for a prolonged period of time, the watch goes into power saving mode which means the LCDs turn off and the hands stop moving. Once it detects light again, or a button is pushed, or the watch is angled toward your face for reading, it awakens again. The LCDs come back on, and the analog hands scurry back into their proper places. Neat trick.
• Atomic timekeeping. This watch will calibrate itself up to five times a day using a radio signal broadcast by the cesium clock in Fort Collins, Colorado (or one of the two atomic clocks in Japan, depending on how the watch is configured). Calibration attempts are made at 1:00 a.m., 2:00 a.m., 3:00 a.m. and 4:00 a.m., and if none of those were successful, again at 5:00 a.m. (if nothing else, this watch is persistent). It chooses late night/early morning with the assumption you are asleep, and the watch is sitting peacefully beside you, dutifully facing Fort Collins near a window. The watch also records the date and time of its last successful calibration, so don't worry about trying to stay awake to monitor it's progress.
• Signal strength indicator. Very handy for finding the optimal spot to let your watch soak up the time calibration rays.
• Analog and digital time synchronization. This means that the hands on this watch are actually just an analog representation of the digital time. This may seem obvious, but Casio actually makes analog/digital watches where this is not the case. You can set the analog hands to be inconsistent with the digital time, but they will still be in-sync, just with an offset between them. I have another analog/digital G-Shock that arrived with the hands way off for some reason, but it was quite easy to get them synchronized, and they have stayed in-step ever since.
• World time. 30 cities (29 different time zones) around the world.
• Five alarms. Each is an independent daily alarm. Nothing special, except that there are five of them. Naturally, there's an hourly time signal, as well.
• Auto-repeating countdown timer. 60 minutes is the timer's ceiling, and it repeats up to nine times. You can turn the auto repeat function off in which case, the left-most LCD (the one at the 9 o'clock position) displays 1/10 seconds rather than the number of times the timer has repeated.
• Stopwatch. Measure elapsed time, split times, and two finishes up to 99:59':99".
• Electro-luminescent backlight. That means only the LCDs are illuminated, not the entire face of the watch. This watch also has an auto illumination function which means, when activated, it will illuminate automatically if you hold the watch parallel to the ground, then rotate it more than 40 degrees toward your face. It's even smart enough not to activate itself if it senses that there's enough light in the room that you shouldn't need it. Pretty slick.
• Water resistant. 20 BAR (20 ATM, 200 meters, or 600 feet).
• Shock resistant. According to the manual, "The watch can be worn on the wrist during any hard sports. (Use care not to allow the front glass to butt against any hard objects.)" Although they don't specify, it should be ok to wear during "soft sports," as well.
• Scratch-resistant mineral crystal.
• Accurate up to about 15 seconds per month. Not exactly an engineering marvel, but consider this: 15 seconds per month is roughly .5 seconds per day (worse case scenario), so if the watch calibrates nightly, at any given time, it should never be more than a half second off, and most likely much less than that. Not bad.

All you have to do is take a survey, and apparently your warranty is extended for an additional year.  It's not clear whether you have to register your watch, as well, however I would assume so.  Registration can be completed online right here.

While I have the attention of G-Shock fans, witness the evolution of the G-Shock through this interactive timeline, or take a peek inside a G-Shock watch.

View photo gallery.

The Casio GW-300 is solid, practical watch for people who are more interested in ruggedness and durability than elegance. It's not the last watch you'll ever buy, or the only watch you'll ever need, but if you're looking for a tough, affordable digital watch, the GW-300 is a good candidate.

Features of the GW-300 G-Shock include:

• Solar powered ("Tough Solar," as Casio calls it). The GW-300 has a rechargeable battery and two discreet solar cells at the top and bottom of the face which are used to replenish the battery. That means unless you're a hermit and live in a cave, you're watch will never be without power.
• Atomic timekeeping ("Waveceptor," as Casio calls it). The GW-300 is equipped with an internal antenna which receives time calibration signals transmitted by an atomic clock on Fort Collins, Colorado. That means assuming you live in an area where the radio signal is detectable (most of North America), you never have to set your watch, and it will always be extremely accurate.
• World time. Easily check the time in 30 different cities around the world (29 time zones).
• Time recorder. Store up to 30 different "snapshots" of the time including month, day, hour, minutes, seconds and the daylight savings mode by pressing a button. Interesting feature. Use it to record the exact time an event occurs. Seems useful for people like firefighters, police, etc.
• Five Alarms. Four standard daily alarms, and one "snooze" alarm which keeps going off every five minutes until you actually go into alarm mode and disable it (as opposed to just pressing a button and turning it off). I really like this feature. I've used it keep reminding me it's time to go to bed.
• Hourly time signal.
• Stopwatch. Display range of 23 hours, 59 minutes, and 59.99 seconds. Measures elapsed time, split times, and two finish times.
• Electro-luminescent backlight. Nice and bright, greenish blueish in color.
• Auto light. If you often need to see the time in the dark, but might not have both hands free (maybe you carry around your baby for hours in the dark trying to get her to fall asleep), turn on the auto light feature, and all you have to do is tilt the watch toward you more than 40 degrees, and the backlight will automatically illuminate. Sometimes takes a few tries, but it usually works pretty well.
• Power saving setting. When power saving is enabled, the watch will enter one of two power saving modes when left in the dark for certain periods of time. Between 60 and 70 minutes of being in the dark, the watch goes into a "light sleep" (all functions except the display are still operational), and after six or seven days, a deeper sleep (in addition to the screen, the beeper tone, backlight, and time calibration function are also disabled).
• Shock resistant. It's a G-Shock, after all.
• Water resistant to 20 bar. That's 20 ATM, 200 meters, or 660 feet. In other words, deep.
• Atomic time signal strength indicator.
• Battery life indicator.