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Casio G-SHOCK GG-B100XMB-1AER Master Of G Mudmaster Black Strap Watch - W17644
Ref. GG-B100XMB-1AER
Sits in Casio’s upper tier here — more premium than three quarters of the Casio watches we list, which start at £25.
Price range £25 to £919 across 129 Casio watches in stock.The Mudmaster line was built around a single demand: to keep functioning when everything else has seized with mud, grit or shock. This XMB variant, released in 2026 as a step up from the standard resin-bezelled GG-B100, swaps in a black ion-plated stainless steel bezel ground to a mirror finish — an unexpected choice for a field tool, but one that gives the watch a coherence the plainer version lacks, the gloss sitting against matte bio-based resin rather than fighting it. At 51.3mm across and 19.4mm deep it makes no concession to discretion, but the Carbon Core Guard structure keeps the whole assembly to 104g, which means it moves with the wrist rather than anchoring it. The Quad Sensor array — compass, altimeter, barometer, thermometer — feeds into the CASIO WATCHES app over Bluetooth, where Mission Log layers the watch's altitude readings onto smartphone GPS route data, turning raw sensor output into something a navigator can actually use after the fact. The strap runs adjustment holes tight enough together to fit cleanly over a bare wrist or a sleeve of heavy outerwear, which for a watch aimed at people working outdoors in variable kit is not an afterthought.
- Reference
- GG-B100XMB-1AER
- Brand
- Casio
- Collection
- G-Shock
- Case size
- 55.4mm
- Case thickness
- 19.4mm
- Case material
- Stainless steel
- Dial
- Black
- Functions
- Stopwatch, Countdown timer, Alarm, Backlight, World time, Perpetual calendar, Bluetooth, Step counter, Compass, Thermometer, Altimeter, Digital display
- Water resistance
- 200m
- Bracelet / strap
- Rubber strap
- Strap colour
- Black
- Retailer
- F.Hinds
Learn more about Casio
Tadao Kashio founded Kashio Seisakujo in Tokyo in 1946 as a machine shop. The company's first success was a finger ring that held a cigarette, and its second was the 14-A of 1957 — the world's first all-electric compact calculator, which used solenoids rather than gears.
Casio entered watchmaking in 1974 with the Casiotron, a digital watch with an automatic calendar that knew the varying lengths of months. The company approached watches as an electronics manufacturer rather than a horological one, and that difference produced the G-Shock.
The G-Shock came from a single engineer, Kikuo Ibe, who broke a watch his father had given him and set out to build one that could not break. The specification was three tens: survive a ten-metre drop, ten bars of water pressure, and ten years of battery life. It took over two hundred prototypes, and the solution was suspending the module inside the case on a cushioned internal structure rather than mounting it rigidly. The DW-5000C shipped in 1983.
It became one of the most durable product designs in any category, adopted by militaries, emergency services, and skateboarders alike, and Casio has since added solar charging, radio and GPS timekeeping, Bluetooth, and full-metal and carbon variants.
Casio also produces the Edifice, Pro Trek, and Oceanus lines, and remains an independent Japanese public company.
- 1946
- Tadao Kashio founds the company in Tokyo.
- 1974
- The Casiotron is Casio's first digital watch.
- 1983
- The G-Shock DW-5000C survives Kikuo Ibe's three-tens brief.
- 1994
- The Frogman extends G-Shock to ISO dive certification.
Manufacturer’s guarantee
What the specifications mean
A watch built to be worn hard and got wet.
Strengths
- 200m water resistance, rated for actual diving
- Second time zone for travelling
- One of Casio's more premium watches
Worth knowing
- 55.4mm is a large watch with real presence
- 19.4mm thick, so it will not disappear under a cuff
Compare alternatives
Watches from other brands at a similar price, style and size, so you can see what else your budget can buy.
| Specification | GG-B100XMB-1AER |  DZ7492 |
|---|---|---|
| Price | £369 | £389 |
| Case size | 55.4mm | 54mm |
| Water resistance | 200m | 30m |
| Movement | Quartz | Quartz |
| Strap | Rubber strap | Leather strap |
| This watch |
|
Your new watch
Frequently asked questions, and things you should know about this watch
Can I swim with it?
Yes. At 200m it is rated for swimming, snorkelling and recreational diving.
Does it need a battery?
Yes. It is quartz, so expect a battery change every two to three years at a jeweller.
Is it a men's or women's watch?
Listed as men's.
Cheapest place to buy
F.Hinds is the only UK retailer we track stocking this reference, so there is nothing to compare it against today.
Who are F.Hinds?
F.Hinds has been run by the same family since 1856 and is now in its fifth generation, with more than 115 shops across England and Wales. They are a member of the Responsible Jewellery Council and an Authorised Diamond Dealer.
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