With the Sony SR521SW battery, you can rest assured, knowing your device will remain powered for long-term use. This silver oxide coin cell is designed specifically for use with low, continuous-drain electronics, such as your analog watch. The non-rechargeable Sony SR521SW is packaged and sold in individual tear strips. When ordering in larger quantities, the silver oxide battery will be packaged in tear strips of five. The Sony SR521SW battery is a reliable power source for your continuous-drain devices.