Adult Powerheart G3 defibrillation pads are stored connected to the AED, a technology developed by Cardiac Science to expedite the rescue process and help ensure electrodes are Rescue-Ready.    Electrode pads are non-polarized to reduce confusion and simplify a rescue.  These pads are compatible with all Powerheart G3 series AEDs (models 9300 and 9390). Electrode pads have approximate 2-year expiration date and the expiration date is clearly labeled on the front of the pad package.