The 7D 24V 50/60Hz INDR BAT BU 21A Time Switch is a universal, electromechanical time control. It is is a light-duty commercial time switch ideal for 24 or 120 VAC single phase applications, such as lighting control, heating, air-conditioning, pumps, motors, fans, agricultural facilities and general electrical circuits. The unit is mounted in a Type 1 indoor enclosure.