Tough Reinforced Plastic Housing, Mount to any surface, Slip-On Inlet and Outlet Ducting Connection, Efficient High Volume Air Flow, Low Current Draw, Corrosion-Resistant Materials Throughout, N.M.M.A. Type Accepted, DC Models comply with USCG Regulation 183.410 and ISO 8846 MARINE for Ignition Protection, DC Models comply with Complies with ISO 9097 MARINE