Casio developed its first calculator in 1957, but it was not until 1974 with the release of the Casiotron that Casio entered the watch making a market. 

G-Shock is a brand of watches manufactured by Casio, known for its resistance to shocks (e.g. hard knocks and strong vibrations). Its full form

Casio developed its first calculator in 1957, but it was not until 1974 with the release of the Casiotron that Casio entered the watch making a market. 

G-Shock is a brand of watches manufactured by Casio, known for its resistance to shocks (e.g. hard knocks and strong vibrations). Its full form is Gravitational Shock. They are designed primarily for sports, military and outdoor adventure oriented activity; nearly all G-Shocks have some kind of stopwatch feature, countdown timer, light and water resistance.

Product Features:

• Shock Resistant
• Triple G Resist
• Mineral Glass / Spherical Glass
• Neobrite
• Case / bezel material: Resin / Stainless steel
• 200-meter water resistance
• Stainless Steel Band
• One-touch 3-fold Buckle
• Solar powered
• World time
• 29 time zones (29 cities coordinated universal time), daylight saving on/off, Home city/World time city swapping
• 1/100-second stopwatch
• Measuring capacity: 23'59.99''
• Measuring modes: Elapsed time, split time
• Daily alarm
• Low battery alert
• Power Saving (hands stop to save power when the watch is left in the dark)
• Full auto-calendar (to year 2099)
• Regular timekeeping
• Analog: 3 hands (hour, minute (hand moves every 10 seconds), second),
• 3 dials (24-hour, world time hour and minutes, day), date
• Accuracy: ±15 seconds per month
• Approx. battery operating time:
• Size of case/total weight: 52.9 X 50.4 X 15.6 mm/152 g