Silver Oxide Batteries are designed for continuous low-drain & high pulse on demand so they are perfect for watches, toys, glucose monitors, calculators & more. At 1.55 volts, the silver oxide / zinc alkaline battery offers higher voltage than comparable mercury batteries & a flatter discharge curve than alkaline manganese dioxide batteries. Mercury-free battery also has good resistance to shock, vibration & acceleration. Cell size is 377. It is a replacement for 376 / 377, 377BP, D377, SB-AW, SR626SW & SR66.