A single Intellisense battery is all that is needed to power your Powerheart G5 AED. This dependable, medical grade battery is tested rigorously at Cardiac Science and then tested each day it is installed in your Powerheart G5 AED for presence and functionality to ensure readiness. Using patented Rescue Ready® technology and embedded circuitry, your Intellisense battery communicates performance condition, age, storage temperature and other vital information directly to your Powerheart G5. Once Intellisense supplies are installed in your Powerheart G5 AED delivers years of unmatched performance. In fact, each Intellisense AED Battery comes with a four year performance guarantee.