G-SHOCK GRB300-1A4 GRAVITYMASTER
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.
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
Carbon Core Guard structure
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
Easy watch setting
Approximately 300 world time cities
Phone finder
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
Day indicator
Regular timekeeping: Analog: 3 hands (hour, minute (hand moves every 10 seconds), second), 3 dials (dual time hour and minute, dual time 24-hour, day)