G-Shock Gravitymaster Watch. GRB300-1A - The "Mach Speed" Analog

The GR-B300-1A is a study in Functional Ergonomics. It features a massive, multi-layered dial that prioritizes instant legibility during high-G maneuvers. The watch utilizes a Carbon Core Guard structure in a seamless, "monocoque-inspired" case that is both incredibly light and exceptionally strong—mirroring the carbon-fiber fuselages of advanced aircraft.

The design language is "Utility-First," featuring a large, dual-time display and a high-contrast black and white colorway with subtle emergency-red accents on the hands and indicators.

Key Performance Features

Aviation-Grade Carbon Core Guard: A carbon-fiber-reinforced resin case that provides superior shock resistance and environmental protection while keeping the watch comfortable for long flights.

Smartphone Link (Bluetooth®): Pairs with the G-SHOCK app to automatically sync to atomic time anywhere in the world and allows for a "Flight Log" function to record time and location data.

Tough Solar Power: High-efficiency solar panels integrated into the dial ensure the high-drain Bluetooth and lighting functions never run out of juice.

Dual Time Display: Features a dedicated sub-dial at the 6 o'clock position to track a second time zone (UTC or Home) at a single glance.

High-Visibility "Cockpit" Dial: Large, luminescent 3D index marks and oversized hands ensure you can read the time even in low-light cockpits or under heavy vibration.

Super Illuminator (High-Brightness LED): A high-intensity LED that floods the analog face with light, making the metallic and luminescent markers pop in total darkness.

200m Water Resistance & Triple G Resist: Specifically engineered to withstand shock, centrifugal force, and high-frequency vibration.

In the Box
Professional Series Packaging, G-SHOCK GR-B300-1A "Gravitymaster," Aviation Tool Manual, and Warranty.