Electronic float switch starts pumps reliably.Dependable, mercury-free, solid-state electronic switch activates pump when water level reaches 2" and deactivates it at 1/2".SpecificationsActivation Method: Solid-state floatAmperage Capacity: 20A @ 6-32V DCDimensions: 2 7/8"H x 2 1/2"W x 5 1/2"LWarranty: Five years