Johnson pumps/Mayfair ultima Bilge Pump Automatic Float switch  PN:36303

Ultima Auto Float Switch for Johnson 12V or 24V bilge pumps. Upon immersion in water, switch automatically turns on. Mercury-free design uses patented detector cells to detect fluids and initiate pumping.

Johnson's unique detector cells are sealed so they are never in contact with the water, won't corrode, and are unaffected by oil or debris.