The Renata Battery SR621SW 364 is a premium quality silver oxide battery. These batteries can be stored for a long time when they have not been opened. This allows you to always have backup at home, without compromising on the quality or longevity of the life of the batteries. These batteries are 1.5 V batteries which fit most of the makes of watches, calculators, digital monitors and scales etc. The batteries are capable of maintaining the flow of power equally throughout its life.