The Powerheart G3 Intellisense® lithium battery is designed for use in Powerheart AED G3 9300E, 9300A, 9390E, and 9390A devices shipped after April 12, 2004. The battery is tested rigorously at Cardiac Science, as well as before installation. Each Intellisense AED battery comes with a 4-year performance guarantee.This product is not a substitute for direct medical attention from a healthcare practitioner. Always read the label and follow the directions for use.