G-SHOCK GRAVITYMASTER – Model GRB300H-5A

Overview

Expand your horizons with a MASTER OF G, designed for pros working in the toughest of environments. The MASTER IN HORIZON GOLD takes its cue from the golden horizon where earth meets sky, pairing rugged capability with refined style.

The bezel is finished in light yellow gold ion plating over a Carbon Core Guard structure built from bio-based carbon, bio-based resin, and stainless steel — strong, and only 71 g on the wrist.

Tough Solar keeps it running from light alone, and Bluetooth® connects it to the CASIO WATCHES app for automatic time correction, approximately 300 world time cities, and a flight log.

Key Highlights

✔ MASTER IN HORIZON GOLD design
✔ Light yellow gold ion plated bezel
✔ Carbon Core Guard structure with bio-based carbon and resin
✔ Tough Solar — solar-powered timekeeping
✔ Bluetooth® smartphone link with the CASIO WATCHES app
✔ Automatic time correction and approximately 300 world time cities
✔ Flight log and phone finder
✔ Shock resistant with 200-meter water resistance
✔ Screw lock crown
✔ Dual time with Home City swapping
✔ Countdown timer up to 24 hours
✔ LED light (Super Illuminator) with afterglow
✔ Full auto-calendar to the year 2099
✔ Power Saving and battery level indicator
✔ Neobrite luminous coating
✔ Lightweight at 71 g

Technical Specifications

Basic Information

• Case Size (L × W × H): 59 × 54.7 × 15.7 mm
• Weight: 71 g
• Case & Bezel Material: Bio-based carbon / Bio-based resin / Stainless steel
• 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: Tough Solar (solar powered)

Exterior

• Glass: Mineral Glass
• Crown: Screw Lock Crown
• Surface Treatment: Light yellow gold ion plated bezel
• Compatible Band Size: 145–215 mm
• Other: Neobrite

Smartphone Link

• Smartphone Link Feature: Mobile link (wireless linking using Bluetooth®)
• App: CASIO WATCHES
• App Connectivity:
  • Auto time adjustment
  • Easy watch setting
  • Approximately 300 world time cities
  • Flight log
  • Phone finder

Watch Features

• World Time: Dual time (Home City time swapping)
• Stopwatch: 1-second stopwatch, measuring capacity 23:59'59, elapsed and split time
• Timer: Countdown timer, 1-second unit, countdown range 24 hours
• Alarm: Daily alarm
• Light: LED light (Super Illuminator) with afterglow
• Light Color: LED: White
• Calendar: Full auto-calendar (to year 2099)
• Energy Saving: Power Saving (hands stop to save power when the watch is left in the dark)
• Battery Alert: Battery level indicator
• Run Time: Approx. 5 months on a full charge with normal use without further light exposure, approx. 18 months when stored in the dark with power saving

Summary

The GRB300H-5A is the MASTER IN HORIZON GOLD GRAVITYMASTER: a gold ion plated bezel over a Carbon Core Guard case, Tough Solar power, Bluetooth time correction, and a flight log, at 71 g with 200-meter water resistance.

GRB300H-5A — Gold GRAVITYMASTER with Tough Solar and Bluetooth.

For more details, visit the official CASIO website here.

Warranty:

• The watch is covered by a official warranty, providing assurance and protection for your purchase.

▶︎Processing Time & Shipping Policy
▶︎Refund policy
▶︎We only carry G-SHOCK USA products.
▶︎Unfortunately, we DO NOT ship internationally.