Leviton T7899-C0I 20A-125V Tamper Resistant Cheetah Light Feed Through Receptacle with LED Indicator, Ivory Mechanical shutter mechanism prevents access to contacts unless a two-pronged plug is inserted Cover made from impact-resistant nylon for longer life The SmartLockPRO receptacle automatically tests the GFCI every time the RESET button is pushed Shutter mechanism inside the receptacle blocks access to the contacts unless a two prong plug is inserted SmartLockPRO diagnoses line-load reversal upon installation as it will not reset if mis-wired