The GR-B300RY-1A9JF is a GRAVITYMASTER model from G-SHOCK’s Master of G Air series. It features Carbon Core Guard structure, shock resistance, 200-meter water resistance, Tough Solar charging, and Bluetooth Smartphone Link through the CASIO WATCHES app.
This model includes world time, stopwatch, countdown timer, alarms, double LED light, and app-linked functions such as automatic time correction, easy watch setting, world time settings, Time & Place, and phone finder.
Specifications
Model
GR-B300RY-1A9JF
Case size
59 × 54.7 × 15.7 mm / 2.32 × 2.15 × 0.62 in
Weight
71 g / 2.5 oz
Case / bezel material
Carbon / Bio-based resin
Band
Bio-based resin band
Structure
Shock resistant, Carbon Core Guard structure
Water resistance
200-meter water resistance
Power supply
Tough Solar solar charging system
Mobile link
Bluetooth Smartphone Link with compatible smartphones
App
CASIO WATCHES app
Glass
Mineral glass
Band size range
145–215 mm / 5.7–8.5 in
World time
38 cities / 38 time zones + UTC
Stopwatch
1/100-second stopwatch, 24-hour capacity, split time
Timer
Countdown timer, up to 60 minutes
Alarms
5 daily alarms + hourly time signal
Light
Double LED light, Super Illuminator
Battery life
Approx. 5 months under normal use / approx. 18 months with power saving
Accuracy
Approx. ±15 seconds per month when not connected to a smartphone
