G-SHOCK 7900 Series – Model G-7900A-4

The G-SHOCK G-7900A-4 is a rugged digital watch designed for those who demand maximum toughness and functionality in extreme environments. Built as a true partner for outdoor, marine, and cold-weather activities, this model delivers exceptional durability paired with advanced tide and moon data.

Design Overview

The G-7900A-4 features a bold, protective design defined by four large bezel screws and a case shape divided into six distinct sections, giving it a strong, utilitarian appearance. Oversized buttons—among the largest in the G-SHOCK lineup—ensure easy operation even with gloves. A large segmented LCD display improves readability by organizing information clearly and efficiently.

Key Highlights

• Shock Resistant construction.
• 200-meter water resistance for marine activities.
• Low-temperature resistance (-20°C / -4°F).
• Moon data & tide graph for ocean and outdoor use.

Specifications

Basic Information

• Case Size (L × W × H): 52.4 × 50 × 17.7 mm
• Weight: 68.2 g
• Case & Bezel Material: Resin
• Band: Resin band
• Construction: Shock Resistant
• Environmental Resistance: Low temperature resistant (-20°C)
• Water Resistance: 200-meter water resistance
• Power Supply & Battery Life: Approx. 2 years on CR2025

Exterior

• Glass: Mineral glass

Watch Functions

World Time

• World Time: 29 time zones (48 cities)
• Daylight Saving: On / Off

Moon & Tide Data

• Moon Data: Moon age of input date, moon phase graph
• Tide Graph: Tide level for specific date and time

Stopwatch

• Stopwatch ST1: 1/100-second stopwatch
  • Measuring Capacity: 999:59'59.99"
  • Modes: Elapsed time, split time, 1st–2nd place times
• Stopwatch ST2: 1/1000-second stopwatch
  • Measuring Capacity: 999:59'59.999"
  • Modes: Elapsed time, split time, 1st–2nd place times

Timer

• Countdown Timer
• Measuring Unit: 1 second
• Countdown Range: 24 hours
• Start Time Setting: 1 minute to 24 hours (1-minute and 1-hour increments)
• Other: Auto-repeat, progress beeper

Alarm & Alerts

• 5 multi-function alarms (with 1 snooze alarm)
• Hourly time signal
• Flash alert: Flashes with buzzer for alarms, hourly signal, countdown timer, and stopwatch auto start

Lighting

• Electro-luminescent backlight
• Auto light switch
• Selectable illumination duration: 3 seconds or 5 seconds
• Afterglow
• Light Color: Blue-Green

Calendar & Accuracy

• Full auto-calendar: Pre-programmed until the year 2099
• Accuracy: ±15 seconds per month

Other Features

• 12/24-hour format
• Button operation tone on/off
• Regular timekeeping: Hour, minute, second, pm, month, date, day

Summary

The G-SHOCK G-7900A-4 is a high-performance digital G-SHOCK engineered for harsh environments and marine conditions. With low-temperature resistance, moon and tide data, oversized controls, and a highly legible display, it is an ideal choice for those who need a dependable, easy-to-read, and extremely tough watch in demanding situations.

For more details, visit the official CASIO website here.

Warranty

All our G-SHOCK watches include the official manufacturer’s warranty for peace of mind and long-term protection.

▶︎Processing Time & Shipping Policy

▶︎Refund policy
▶︎We only carry G-SHOCK USA products.
▶︎Unfortunately, we DO NOT ship internationally.