Meets new 2008 NEC Code tamper resistant requirements. Helps prevent improper insertion of foreign objects. UL 943-2006 compliant. Lock out function will not allow GFCI to reset if miss-wired. End of life function stops voltage in the event of a GFCI component failure. 125 Volt AC. 8 back wiring holes and side wire screws accept up to 12 gauge wire. LED status indicator, color matched wall plate and screws.