Saving energy can save you money. By installing a timer to control a light or fan, you'll be able to enjoy your light or appliance for a period of time without remembering hours later that you've left it on. The Spring-Wound Wall Switch Timer will turn off its load after 15 minutes, ideal for a closet light or air conditioning unit that doesn't need to run constantly. A switch plate is required and sold separately. # Gangbox # Timer plate # Timer wheel # Mounting materials # Instructions.The Spring-Wound Wall Switch Timer is as easy to install as a light switch in a standard 2 1/2-inch deep vertically installed junction box in place of a standard single-pole, 3-way, or double-pole single-throw wall switch. The timer will automatically turn off lights, fans, air conditioners and other energy-consuming loads after a preset timing period, and since the unit is spring-wound, it uses no electricity. An exclusive "up front" terminal connection with teeter type terminals and an easy "press-on" knob design ensure quick and easy installation. The Spring-Wound Wall Switch Timer is also available in white; 1-hour, 12-hour, and 30-minute switch timers are also available.