The Smith ' Wesson Heartbeat AED uses the "1-2-3" rescue approach, which is ideal for the non-medical user. By following text messages together with voice prompts, virtually anyone can operate this lifesaving device. The instrument automatically determines if a lifesaving shock is required and protects against inappropriate delivery of a shock. At just 3 1/2 pounds, the Heartbeat unit is small, lightweight and portable using a long life lithium battery, and has a rapid 5-second charge cycle.