For an added layer of protection, the GFCI regularly conducts an automatic internal test to confirm that it can respond to a ground fault Provides continuous ground fault protection - detects and trips on ACTUAL ground fault even when self-test is being conducted 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. Total outlet: 2 Slim, shallow design - reduced depth makes it easier to install in any electrical box, even shallow ones Wallplates not included