Leviton 7899-SGI Smartlock Pro Ground Fault Circuit Interrupter Receptacle; Phase 7 Design, NEMA 5-20R, 20A-125V, Lighted Test and Reset Button, Ivory Automatically test the GFCI every time the RESET button is pushed in, The GFCI will not reset if the GFCI circuit in not functioning properly By blocking reset of the GFCI if protection has been compromised, SmartLockPRO reduces the possibility of end-users incorrectly assuming that a reset GFCI outlet is providing ground fault protection when it actually is not A line-load reversal diagnostic feature is provided which prevents the GFCI from being reset and stops power from being fed to the GFCI receptacle The trip latch mechanism in SmartLockPro GFCIs is a one piece "T" design for efficient operation There are 4 sets of contacts for load terminals and face & SmartLockPRO GFCIs use a patented bifurcated bridge contact for efficient operation