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MASTER OF G - LAND
MUDMASTER

GG-B100X-1A9

NEW 02/2026
My GShock

Built for fearless explorers and lovers of the great outdoors, the Master of G MUDMASTER is a tough, rugged timepiece engineered for extreme conditions. Featuring a bezel and case made from high-strength carbon and environmentally responsible materials, it delivers uncompromising durability where it matters most. Part of the G-SHOCK Master of G range, developed for professionals operating in the harshest environments, the MUDMASTER raises the bar even further. Designed to withstand the most demanding on-land conditions, it has earned the confidence of rangers and rescue teams working in extreme terrain. The GG-B100 MUDMASTER uses a high-rigidity carbon case to minimise damage and distortion, while ensuring exceptional airtightness and shock resistance. A mud-resistant filter structure, stainless steel case back, and shock-resistant resin back cover reinforced with glass fibres provide outstanding protection against dust and mud. The bezel incorporates a three-layer resin construction with carbon fibre inserts, while the rugged design takes inspiration from the fuel jerrycans found on off-road vehicles built to conquer the toughest landscapes. Key resin components in the case and band are made from bio-based resin derived from renewable resources, helping to reduce environmental impact. Designed with practicality at its core, the watch is equipped with a digital compass, altimeter/barometer, thermometer and step counter. Time can be easily adjusted via the CASIO WATCHES app, which also unlocks useful features such as Mission Log. This function automatically records altitude data from the watch and route data from your smartphone. When conditions are at their toughest and decisions matter most, the MUDMASTER is a dependable tool you can trust to perform.

Specifications

FEATURES

Shock-, dust-, and mud-resistant structure delivered by carbon fiber-reinforced resin

Offering strength, lightness and excellent weather resistance, a carbon fibre-reinforced resin case protects the module. Gaskets are applied around the buttons to ensure a tight seal, providing reliable dust and mud resistance even in harsh environments. Carbon fiber-reinforced resin is also used for the cover enclosing the case back and for the movable parts on the underside of the band, enhancing both durability and wearing comfort.

*Image shows the GG-B100XM-1A.

Direction Measurement Display Image

Digital compass

Altimeter Display Image
Barometric Pressure Measurement Display Image

Altimeter/Barometer

Temperature Measurement Display Image

Thermometer

Step count display range:

Step counter

Quad Sensor supporting land missions

In addition to the triple sensor that measures compass bearing, altitude/barometric pressure, and temperature, the watch is equipped with an accelerometer for step counting. By collecting diverse data, the Quad Sensor makes it easy to monitor environmental changes and track activity history, helping ensure reliable performance in land missions under the toughest conditions.

*Image shows the GG-B100XM-1A.

Bio-based resin image of GG-B100X

Bio-based resin

Key resin components used in the case, band, and more are made with bio-based resin.

* Image is included for illustrative purposes only.

Smartphone Link Model

Smartphone Link

The watch connects to a smartphone via Bluetooth® to automatically adjust the time. Using the dedicated app, various watch settings and mission logs can be managed with ease.

A photo of GG-B100XM lit up

Super Illuminator

Super Illuminator (high-brightness auto double LED light) for maintaining watch readability in the dark

*Image shows the GG-B100XM-1A.

Review

*The color tone of the listed products may differ from the actual product in some cases.

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