Casio G-Shock GM2100-1A

From G-SHOCK, the toughness watches that continue to evolve in search of ultimate strength, this digital-analog combination model inherits the concept of the first-generation DW-5000C models, while being even thinner. Inherits the octagonal shape that was also used in the first-generation DW-5000C model. A combination model developed with a simple design that eliminates waste while maintaining a tough structure. Also achieves a thickness of 11.8 mm thanks to a highly rigid fine resin containing carbon fiber for the case material.

31 time zones (48 cities + coordinated universal time), daylight saving on/off

1/100-second stopwatch 00'00''00~59'59''99 (for the first 60 minutes) 1:00'00~23:59'59 (after 60 minutes)
1/100 second (for the first 60 minutes) 1 second (after 60 minutes)
measuring modes: Elapsed time, split time, 1st-2nd place times
countdown timer
countdown start time setting range: 1 second to 24 hours (1-second increments, 1-minute increments and 1-hour increments)
LED light for the face (Super illuminator, selectable illumination duration (1.5 seconds or 3 seconds), afterglow)
LED backlight for the digital display (Super illuminator, selectable illumination duration (1.5 seconds or 3 seconds), afterglow)
auto-calendar (to year 2099)
12/24-hour format
Hand shift feature (Hands move out of the way to provide an unobstructed view of digital display contents.)
Regular timekeeping:
Analog: 2 hands (hour, minute (hand moves every 20 seconds)), 1 dial (day)
Digital: Hour, minute, second, pm, month, date
battery life: approx. 3 years
accuracy: ±15 seconds per month
case diameter: 44.4mm
case height: 11.8mm