Automatically test the GFCI every time the Reset button is pushed in. The GFCI will not reset if the GFCI circuit is not functioning properly. * Reduced depth of SmartlockPro Slim GFCI makes it easier to install in any electrical box, even shallow ones. * Terminals allow for easy wiring options ? back and side wire capable. * Trip threshold meets or exceeds UL requirements for tripping time. * Limited 2-year warranty