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The Casio GW-7900B-1ER is a shock-resistant, solar-powered digital watch featuring world time across 48 cities, 20 bar water resistance, and a durable yet comfortable matte resin strap. Designed for professionals who demand reliability and style in harsh conditions, it combines advanced atomic timekeeping with practical functions like tide and moon phase info, all in a sleek, lightweight package.









| ASIN | B0039YOIH0 |
| Age Range Description | Adult |
| Band Colour | Grey |
| Band Length | 21 Centimetres |
| Band Material Type | Plastic |
| Band Width | 18 Millimetres |
| Bands | 1 |
| Best Sellers Rank | 270,149 in Fashion ( See Top 100 in Fashion ) 1,908 in Men's Wrist Watches |
| Brand Name | Casio |
| Case Diameter | 50 Millimetres |
| Case Material Type | Stainless Steel |
| Case Thickness | 18 Millimetres |
| Character | Fashion |
| Clasp Type | Buckle |
| Closure Type | Snap |
| Crystal | Crystal |
| Customer Reviews | 4.4 out of 5 stars 2,885 Reviews |
| Dial Color | Black |
| Display | Digital |
| Embellishment Feature | Crystal |
| Face Style | Minimalistic |
| Global Trade Identification Number | 04971850435211 |
| Included Components | 1 item |
| Item Shape | Round |
| Item Type Name | Watch |
| Item Weight | 71 Grams |
| Manufacturer | CASIO |
| Manufacturer Warranty Description | 2 years |
| Model Name | GW-7900B-1ER |
| Model Number | GW-7900B-1ER |
| Pattern | Solid |
| Power Source | Solar Powered |
| Series Number | 7900 |
| Sport Type | Other Sports |
| Strap Type | Resin |
| Style Name | Bracelet |
| Warranty Type | Manufacturer |
| Watch Movement Type | Quartz |
| Water Resistance Depth | 200 Metres |
| Water Resistance Level | Not Water Resistant |
P**Y
Great fitting, large G-Shock with a soft matte resin strap.
This is by far one of the nicest G-Shocks that I have come across. The face is chunky, depth wise, and so might not get along with a tight fitting cuff. But because this is a solar charged watch I tend to let it sit outside the cuff and Its usually worn in casual clothing anyway. I find this watch to be very cool looking and stylish, even though is designed to target the Rescue service market. It doesn't look out of place in any situation other than when wearing a suit. It's also worth noting that I have a very small wrist and I found the new mudman too big for me and it just didn't 'hug' my wrist like this model does. And because the strap is soft and matte it makes it even better and there isn't lots of excess strap sticking out which I find with most G-Shock. It's also I very light! I kinda wanted a bit of weight to this but it's so light. You can be guaranteed of very accurate timekeeping too due to this watche being atomic, meaning that it updates the time every day making it accurate right down to the seconds. Of several negative displays I have come across in the G-Shock range this one is the easiest to read but I do find myself using the light often enough. In terms of functions this watch has all you need and more for the average guy and it all works very well. My only complaint is that this watch has frozen on me twice and I've only had it a month. If this happens to you, you can press three buttons at once to reset it. I think it's the two buttons on the left and one of the buttons on the right. This works for a lot of G-Shocks if they freeze or act up on you. Overall this is a nice fitting stylish and functional rugged watch and I'd recommend it to people in the services (if the thickness of the watch won't be an issue) and to G-Shock fans/collectors who like a stylish G! (Eminem wears this G! Which will help sales!) I'm not a very good reviewer but I hope this helps answer some questions buyers may have.
S**N
Well-balanced, one of the best G-Shocks out there
This G-Shock hits the sweet spot between price, quality & features. It includes tide & moon phase info, several alarms (incl. snooze alarm), stopwatch & timer, world time & multi-band 6 (radio synchronisation with atomic clocks), an inverted digital display that looks fantastic (though it does sacrifice visibility for looks, so if you want visibility get the standard black-text-on-white-background version) and solar-powered battery. It’s not the largest G-Shock and definitely not a Master of G or one of the more luxury-oriented ones, but if you’re looking for a tough, great looking & reliable watch to use as your daily workhorse, during tough jobs or trips and not worry about damaging it (did I also say it looks great?), and you want or need a couple of neat features like tide & moon phase, you cannot go wrong with this choice. The auto-illumination feature (the face lights up when you move your wrist to look at it) is also practical and mitigates the reduced visibility of the inverted display that wouldn’t be legible without it at night or in a dark location otherwise. A steal for the price & features, and in my opinion a well-balanced piece that gets the best Casio G-Shocks have to offer.
I**H
Amazing work watch but style comes with a big price premium.
There are so many reviews online of this watch that the spec hardly bears repeating but what do I think? Classic G-Shock case design though slightly oversized to make it appear bulletproof. Makes it hard to slide slim or tailored cuffs over it due to the increased height. Despite the size it doesn't actually look too big on the wrist and is very comfortable due to the additional 'wings' covering where the strap meets the case. Multiband 6, Tough Solar and the usual G-Shock features mean it is a watch that is truly accurate and should need virtually no maintenance. Looks fabulous in the black with the negative LCD. After reading the reviews I was actually surprised how easy it was to read. I can see it isn't for everyone but combined with the automatic backlight I have never had a single issue reading the display. Due to the darker display it is perhaps slightly more affected by reflections but with the right light the digits really stand out just like the photos. The only disadvantage worth noting is that you pay a big price premium over the standard watch to have the black version. It was a style choice for me in the end and I am glad I made it but it is hard to justify the extra money for any other reason. I assume it is so much more because this model isn't a UK official watch (it doesn't appear in the Casio UK website) but rather one destined for other markets.
F**T
Another superb Casio
The good: - Build quality and attention to detail. - Comprehensive list of features. - Ease of use - logical design and layout. - Comfortable to wear. - Rugged, high-tech looks. - Negative display surprisingly easy to read in bright light (but see comments under 'The bad'). The bad: - Readability of the negative display suffers badly under low light conditions (unless you have the auto back-light enabled). - Alarms and other audio signals are too soft. Overall: This is a very nice watch of typical Casio quality (I've owned many Casio watches in my time and I've never been disappointed when it comes to quality and reliability). Admittedly, my objections against the negative display may be somewhat subjective and many people may not even care about that - it is probably as much of a fashion statement as anything else, and some people may buy it for that reason alone; still I would advise any potential buyer to first try and view one first hand and compare with a positive display before making up their minds. Secondly, I'm someone who really finds a lot of use for alarms and a count down timer in a watch, but in a daily setup with normal background noise (e.g. office setting) the alarms are often inaudible. If you don't care about these points, I would recommend the GW-7900B without hesitation. Finally, 5-star rating for Amazon's handling of the order. Product was dispatched the day after placing my order and arrived at my doorstep (in South Africa) in less than a week.
G**E
Sturdy and reliable!
I bought this particular model because it shows the phases of the Moon and the state of tidal flow. I find this handy as I live on the shore of a sea loch and own a small boat. The Moon phase is set automatically and is linked to your chosen city while the local tide times can be set manually. It is also waterproof. My other main reasons for purchase were that the time setting is radio controlled and the watch is solar powered. The first more or less guarantees accuracy whilst the second saves bothering about changing batteries. It has a number of other functions, such as alarm and stopwatch, but I will probably not use them. They are also handy to have, however, as available options. My use will tend to be local, but World Travellers can easily adjust the watch to suit their travels. The main display is digital with a neat calendar. I understand some have difficulty reading the display, but I don't. It would be hard to describe it as a dress watch. It is large and chunky on the wrist, but the strap fit is really comfortable. I bought it as it is specifically designed to be unaffected by knocks and shocks normally experienced in active outdoor pursuits and, for this purpose, I think it not only looks the part, but actually is the part.
M**E
In the context for what it does - its perfect. I use it for working out
I have had this watch for 1-2 years now. Its a superb watch. Remember people this is a watch that will not make you cry if you break or lose it. In the context for what it does - its perfect. I use it for working out, circuit/HIIT training/Swimming/ and as a timer at work. The buttons are so easy to press. It has come to the point that I can press buttons and remember watch positions without having to look at the watch itself. Great for using therefore when carrying out movements and you just need to quickly start or stop the stop watch. I have really integrated this watch into my lifestyle for all manner of things - cooking, cleaning, brushing teeth - its fun. Watch as we know can't be spoiled by any liquids etc. I will say just one thing. As a United Kingdom resident (we get debatable sunshine), and further working in an office with no windows - I did find it initially challenging to get the solar charge up to its highest. It took a few weekends of taking the watch off and leaving it in the garden to help the charge get to its full capacity. I found its better to just block out a day watch free and get some focused charge done. The instruction manual communicates that it takes longer to charge it from Medium to High. Once you get to High - you just need to top it up every now and then. FYI since now having this watch for 2 years, the solar battery life only has to be cared for if you have the automatic light switched on with wrist movement. As a UK resident if you have this function switched off and your happy to switch on the light manually - no solar battery charging ever has to be thought of. Secondly, and I was ready for this (as had read about it). One of the 4 screws may fall out. They don't screw in - they clip in. I contacted Casio and they easily sent a replacement me for a few pounds. There are some other mild criticisms such as if I am in the dark and I want to navigate around watch functionality - I would repeatedly need to keep pressing the light button (which is timed before it cuts out). Remember the price your paying. If I lost this watch - I wouldn't care. I can see this watch being by my side easily for 10 years.
J**S
Alarm barely unusable, battery lasts 3 days.
After much though i went for this simpler less frills than the past that seem to only last two years. Paid extra for the inverted display and soon found out its hard even very awkward to read dependant upon the light and also under clothing peeling back. I was going to send it back after 1hr, alarm was useless with 1 bleep. Cover over with clothing and wont hear. Then figured using the other 4 alarms it offers several bleeps but still too quiet. Solar charging is pretty good and the radio updates work well, the only reason for not sending it back.
I**N
G-shock are the best.
So I decided to invest in another g-shock for my collection. Definitely the most rugged and versatile watch that have ever been made. Definitely a go anywhere do anything watch. The colour is good with the black making it very discreet looking which makes me feel like I’m in the special forces or something 😄 It’s very easy to adjust but I did need to watch a YouTube video to get it right. As with any g-shock the water resistance is excellent at 200m. As it’s a multi band 6 watch it links up to the atomic clock every night if it gets a signal so the accuracy should always be spot on and you should never need to worry about adjusting it. I’ve had this on now for a couple of hours and for a big chunk on my wrist you definitely wouldn’t notice it so it’s a nice weight. As it’s from Casio it’s definitely value for money and will definitely be a great addition to my collection. Pros…Great watch that really is indestructible and accurate. Cons…Still getting used to the negative display. I’d definitely recommend this watch to anyone.
Trustpilot
4 days ago
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