Unlike other AEDs, the Powerheart's patented RescueReady technology tests not only the battery system components, but also verifies that the pre-connected disposable electrode pads can properly deliver a shock. So you can be confident it will work the first time, every time. With this superior performance, plus impedance-compensated biphasic waveform and easy one-button operation, it is the AED with the PhD. Return Policy30 Day Return Policy. Free Return. 60 Day warranty, money back guaranteed!