swimming pool filter timer:

A 24-hour repeating outdoor timer specially designed to control the aboveground swimming pool filter pumps. It can also be used to turn ON and OFF portable spas, engine block heaters and other appliances or equipment that require twist-lock receptacles. It offers multiple on-off settings per day, each set with trippers. It may be manually overridden when needed. This timer can be used indoors or outdoors and is equipped with a weather resistant cover.

pool filter timer