Black Casio G-Shock GA-100-1A1ER Watch The black Casio G-Shock watch has a striking 51 mm wide case made of durable resin. The watch strap is also made of black resin. The stylish Casio G-Shock watch is shockproof and waterproof. The watch has an LED backlight, world time, timekeeping features, average speed measurement and many other useful features: LED backlight Timer Timing (1/100 s accuracy) Average speed 5 alarms 12/24 hour display World Time (29 time zones) Automatic calendar Day of the week display Special impact resistant Waterproof: 200m Body width 51 mm Material: resin Color: black Mineral glass Battery life: 2 years Casio is a Japanese manufacturer of electronic devices, which is especially known for its high-quality and durable sports watches. Casio watches have versatile features and are suitable for both extreme sports and active everyday life. Casio watches are also popular among conscripts due to their durability and excellent value for money. See all Casio products here