Made of Genuine Leather, Stainless Steel Strap/Band Width: 20mm for 40mm Case Case Size: 40mm, 7mm Thin Water Resistance: 3 ATM Battery: SR621SW Interchangeable Genuine Leather band: the quick release function of Arvo Watch Bands makes them easy to switch out in a minute or two without tools split Arvo Awristacrat gold watches for men and women are a statement in style and class for those who aren't afraid to step up their game. The upgraded stainless steel casing and backplate offer durability while maintaining a slim profile. There is also sophisticated date and weekday windows in a way that is unique to Arvo. Note for travelers and night owls - The mechanism that controls the switching of the 'Day' window happens over a 3 hour period, beginning at midnight and completing the transition at 3:00am. If your watch is not doing so, set the time ahead 12 hours and your watch will be correct again.