The Defibtech Lifeline AED range offers the following unique features over all other defibrillators:  Proven to be the easiest to use AED on the market by several independent studies  8-year warranty – the only defibrillator on the market to offer this length of warranty  Unique high capacity battery option available (AED & AUTO)  Free software upgrade if the resuscitation guidelines change (other manufacturers may charge for this)