The G-Shock GM2100M-1A is a men's watch from the 2100 series, featuring a black colorway.

• Resin and stainless steel construction
• Bio-based resin band
• Mineral glass
• Shock resistant
• 200-meter water resistance
• World time with 31 time zones
• 1/100-second stopwatch
• Countdown timer
• 5 daily alarms
• Hourly time signal
• Double LED light
• Full auto-calendar up to year 2099
• Button operation tone on/off
• Accuracy: ±15 seconds per month
• 12/24-hour format
• Dimensions: 49.3 × 44.4 × 11.8 mm
• Compatible band size: 145-215 mm