The Intermatic T103 Electromechanical Timer is a heavy-duty switch designed for wall mounting. It has a rotary switch style and a double pole single throw contact configuration. The timer is suitable for both interior and exterior use and is weatherproof and dustproof. It has a 24-hour timer and can be set to switch on and off once a day. The timer has a screw terminal electrical connection and is compatible with incandescent bulbs.