A tiny battery can keep an entire watch running, yet choosing the right one is surprisingly easy to get wrong. The 335 is a specific silver oxide watch battery, also identified as SR512SW. It has a nominal voltage of 1.55V and measures approximately 5.8 mm in diameter and 1.6 mm in height. For anyone shopping for Watch Batteries 335 Online, those specifications are the starting point. The goal isn\'t simply to find a battery that looks similar. You need a cell that matches the device\'s required size, chemistry, and electrical characteristics. That matters whether you\'re replacing one watch battery at home or stocking supplies for a repair business.