When a sudden cardiac arrest occurs, only half of the victims will need a shock, but all will require cardiopulmonary resuscitation (CPR). ZOLL's Fully Automatic AED Plus is an automated external defibrillator (AED) that helps a rescuer save a life. Any bystander can take ZOLL's AED Plus to the victim of a sudden cardiac arrest and follow the instructions on the device. From placing the electrode pads on the victim's chest to delivering a shock to restart the heart, the ZOLL AED Plus provides instructions and assistance throughout the entire procedure. ZOLL's AED Plus features Real CPR Help, a CPR feedback tool that is able to know what the rescuer is doing. The device will tell the rescuer to do chest compressions harder or faster, and advises when CPR is being done properly. If the defibrillator detects an opportunity to deliver a shock, it will instruct the rescuer to stop chest compressions while it automatically shocks the victim's heart. A four year study in Arizona showed that survival from out-of-hospital cardiac arrest (OHCA) more than doubled when emergency medical providers utilized ZOLL defibrillators.