The Casio GM-2100B-3AER G-Shock - Octagon watch combines a 44mm octagon shaped green ion-plated stainless steel case and green resin strap with a traditional buckle. It has a green dual display dial which is protected beneath mineral crystal glass. Power is generated by the quartz movement. This model also has a water resistance of up to 200 metres. Countdown timer Shock-resistant Shock-resistant construction protects against impact and vibration. Stopwatch function World time function Displays the current time in major cities and specific areas around the world. - Case Depth 11.8mm - Case Width 44.4mm - Watch Movement Quartz - Water Resistance 200 metres