G-Shock • GRB300-1A • Gravitymaster Watch

The sky’s the limit! Introducing the GRAVITYMASTER GRB300, a piece of aviation-inspired professional gear designed to work even in the harshest environments, from the G-SHOCK MASTER of G line.

The GRB300 features a Carbon Core Guard structure, which delivers the shock-resistance, rigidity, and corrosion-resistance of carbon material used in aircraft fuselages. The carbon fiber-reinforced resin case and the seamless bezel design inspired by next-generation aircraft come together in a bold and powerful form. 

Envision the world through a pilot’s eyes with the flight log memory function for recording current location and time, as well as dual-time simultaneously displaying the time in two time zones. In addition, simply tap on the app to instantly switch between the time back home and local time — a practical function to make traveling abroad that much smoother.

Large, dimensional index marks and a metal bezel accentuating the large watch face exude functionality, enhancing the visibility that is so important for pilots, whose job demands intuitive reading of time.

The rotary disc indicator at the 9 o’clock position uses a dual-coil motor to ensure smooth rotation and functional beauty. The indicator not only rotates to display alarm on/off and stopwatch; it functions as a battery level indicator as well.

The high-contrast black and white color scheme dotted with color accents on the dial and buttons evokes the look of a cockpit instrument panel, while dark color variations express the practical functionality of an aviation worldview.

Key resin components used in the case, bezel, and band are made with bio-based resin, a material expected to help reduce environmental impact.

FEATURES

• Case size (L× W× H): 59 × 54.7 × 15.7 mm
• Weight: 71 g
• Case and bezel material: Carbon / Bio-based resin
• Band: Bio-based resin band
• Construction: Shock Resistant
• Water resistance: 200-meter water resistance
• Time adjustment: Bluetooth: Connects to a smartphone and automatically adjusts the time
• Power supply and battery life: Tough Solar (Solar powered)
• Smartphone Link feature: Mobile link (Wireless linking using Bluetooth®)
• Apps: CASIO WATCHES
• App connectivity feature: Auto time adjustment
• Glass: Mineral Glass
• Crown: Screw Lock Crown
• Compatible band size: 145 to 215 mm
• Other: Neobrite
• World time: Dual time (Home City time swapping)
• Stopwatch: 1-second stopwatch Measuring capacity: 23:59'59. Measuring modes: Elapsed time, split time
• Timer: Countdown timer Measuring unit: 1 second Countdown range: 24 hours Countdown start time setting range: 1 minute to 24 hours (1-minute increments and 1-hour increments)
• Alarm/hourly time signal: Daily alarm
• Light: LED light (Super Illuminator) Afterglow
• Light color: LED:White
• Calendar: Full auto-calendar (to year 2099)
• Energy saving feature: Power Saving (hands stop to save power when the watch is left in the dark)
• Battery display/alert: Battery level indicator
• Run time: Approx. battery operating time: 5 months on rechargeable battery (operation period with normal use without exposure to light after charge) 18 months on rechargeable battery (operation period when stored in total darkness with the power save function on after full charge)
• Accuracy: Accuracy: ±15 seconds per month (with no mobile link function)
• Other features: Date display