The Duracell 389 390 1.5V Silver Oxide Watch Battery is a high-quality, long-lasting coin/button cell battery perfect for various applications such as calculators, toys, security devices, watches, and low drain devices. With a dimension of 11.6mm x 3.1mm and a voltage of 1.5V, this battery is designed to provide reliable power for extended periods. The Duracell brand is known for its long expiry date, making it a dependable choice for everyday use.