Rule Bilge Pump - Automatic - 500 G.P.H. - 12VCaracteristicas: Hidden air vents in the pump body prevent air locking in the plumbing installations and help with the check valve Automatically removes water from engine compartment; cycles every 20 seconds to check for water Back flow protection reduces the amount of water left in the bilge to keep it cleaner Built in thermal cut off (TCO) provides added protection for the pump and vessel 12V (1. 9 amp draw) and unmatched in pumping power and