Shutter mechanism inside the receptacle blocks access to the contacts unless a two-prong plug is inserted, helping ensure hairpins, keys, etc., will be locked out * The SmartlockPro receptacle automatically tests the GFCI every time the RESET button is pushed * The GFCI will not reset if the GFCI circuit is not functioning properly * Wiring module locks and latches to the receptacle body providing double the connection security * Large triple-wipe, brass "T" line contacts on 20A for superior contact and conductivity