The Mk5 double action pump consists of two Mk5 pumps mounted back to back and operated by the one handle. It may be fitted either to the floor/deck, or through the deck with purchase of optional through deck conversion kit. Twin diaphragms allow the Mk5 double action pump to empty two separate bilge compartments at the same time, or one twice as quickly using the two manifolds supplied. Even if one bilge runs dry, pumping of the other can continue unimpaired. Suitable for saltwater, bilge water, waste water, effluent and diesel. Made from aluminium alloy, stainless steel, phosphor bronze, acetal copolymer, polypropylene, nitrile rubber and neoprene rubber.