Casio G-Shock Gravitymaster GR-B300H-5AER Men's Watch • Tough Solar • Bluetooth

The Casio G-Shock Gravitymaster GR-B300H-5AER is a high-performance watch from the acclaimed Master of G line, engineered specifically for pilots and professionals operating under the most demanding conditions. Its rugged Carbon Core Guard construction, crafted from bio-based carbon and bio-based resin, delivers a case that is both exceptionally lightweight and highly impact-resistant. The bold design is defined by a metal bezel with a bright yellow gold ion plating, while key metal components are accented with a brown ion plating finish. The dark brown bio-based resin strap completes the powerful presence of this watch, which draws its inspiration from the golden horizon where earth and sky converge.

Thanks to Tough Solar charging and Bluetooth connectivity via the CASIO WATCHES App, the watch synchronises automatically with your smartphone. Large, three-dimensional index markers and a high-contrast dial layout provide the intuitive legibility that is essential in the cockpit. The subdial at 9 o'clock is driven by a twin-coil motor and serves simultaneously as an alarm status indicator, stopwatch display, and battery level gauge. Neobrite luminous material and LED illumination ensure optimal visibility even in low-light conditions.

Key Features of the Casio GR-B300H-5AER Watch

• Tough Solar with Bluetooth: Solar power combined with automatic time synchronisation via the CASIO WATCHES App and access to approximately 300 world time cities.
• Carbon Core Guard structure: Case constructed from bio-based carbon and resin with a stainless steel bezel finished in gold ion plating, offering maximum protection at minimum weight.
• Water-resistant to 20 bar with a screw-lock crown, stopwatch, countdown timer, world time, dual time, and a fully automatic calendar through to 2099.

Care Instructions for Wristwatches

Care & Cleaning

• Daily: Wipe the case and bracelet with a soft, dry cloth to remove dirt and perspiration.
• Water-resistant watches: Clean with mild soapy water and a soft brush, rinse, dry thoroughly.
  Important: Screw the crown down firmly beforehand!!!
• Not water-resistant: Clean only dry or slightly damp, do not use water or cleaning agents.
• Avoid: Aggressive agents, perfume, cosmetics and heat.
• Leather straps: Do not soak, clean only slightly damp and allow to dry away from heat.
• Water resistance: Do not wear in the shower or bath, have checked annually.
• Battery (quartz): Have a depleted battery replaced immediately.
• Mechanical watches: Service by a master watchmaker every 5 years.

Storage & Handling

• Store the watch separately, not directly with other jewellery (risk of scratching).
• Place mechanical watches on a flat surface when winding, do not leave the crown pulled out.