With the slimmest profile on the market, the device allows for fast and easy installation, while Leviton's patented reset lockout mechanism prevents reset of the GFCI if it is not wired or operating correctly. The SmartlockPro Self-Test GFCI is the smart choice in ground fault circuit interrupter protection. Provides continuous ground fault protection - detects and trips on actual ground fault even when self-test is being conducted On initial power up, tests the GFCI within 3 seconds Auto-monitoring exceeds the UL requirement Auto adapts and shifts to more frequent testing if potential problem is detected Status indicator light provides simple, intuitive feedback on power and protection status as well as indication of line/load reversal Patented lockout action prevents reset if GFCI is damaged and cannot respond to a ground fault Electronics are designed to minimize any false triggers Reduced depth makes it easier to install in any electrical box, even shallow ones Terminals allow for easy wiring options - back and side wire capable External back wire clamps provide visual indication of proper wire seating Withstands high torque and resists wire pullout Stainless steel strap and screws, cold impact resistant face and buttons Trip threshold meets or exceeds UL requirements for tripping time