Mechanical timers simplify your life by automating repeating parts of your schedule, saving you time, energy and money. The W400B is a 7-day timer, ideal for heating and ventilation systems, air conditioners, lighted signage, displays and storefront lighting. Use this timer to set up to two different ON/OFF schedules for each day of the week. The W400B includes 7 pairs of trippers (and will accommodate 7 more), a skip-a-day function, manual override, 4PST output contacts and a NEMA 1 metal enclosure. Additionally, it is UL-Listed for 120V, 60Hz loads. When choosing a mechanical timer, trust in the name of TORK, a pioneer in the time switch industry since 1922.