In-Wall Smart Toggle Switch with QuickFit and SimpleWire enhancements. Revolutionary QuickFit design features a housing depth that is up to 20 percent smaller than the previous Z-Wave models. This reduced size coupled with the elimination of heat taps provides a better fit in older style boxes and multi-gang configurations. SimpleWire technology allows line and load to automatically be configured with auto-sensing line-load terminals. All of this is coupled with Z-Wave S2 and Smart Start allows for effortless installation while being safer than ever!