DEFIBTECH 4 year Battery for Lifeline View/ECG/Pro AED – This replacement battery is for your Lifeline View/ECG and Pro AEDs. It is not for the Lifeline Semi and Fully Auto AEDS. This battery can deliver up to 125 shocks or 8 hours of continuous monitoring. Comes with a standby life of 4 years when installed in the unit including the daily, weekly, monthly and quarterly self-tests of the AED. If the battery is getting low it will emit an audible “chirp”. You can check the status indicator next to the On/Off button, it should be flashing green, if not, just press the center button of the three softkeys buttons to the right of the display screen to activate the screen. It will show you the amount of battery life remaining. Always leave the battery in the AED unless you are replacing the battery. DEFIBTECH 4 year Battery for Lifeline View/ECG/Pro AED comes with a 4-year manufacturer’s warranty with the expiration date printed on the manufacturers label that is affixed to each battery.