Philips HeartStart OnSiteThe Philips HeartStart OnSite assists you through the process of treating a victim of suspected sudden cardiac arrest (SCA) and is the only AED available over the counter. The OnSite AED provides practically real time guidance through step by step voice commands and CPR guidance. Patented Quick Shock feature allows the OnSite to typically deliver a shock within 8 seconds after CPR Includes features to help guide the treatment of sudden cardiac arrest