UP15-42F wet-rotor, cast iron circulator pump with a 1/25 HP, 3450 RPM, 115v, single phase motor for hydronic heating in closed loop systems. Flange gaskets are included, but flanges are sold separately. Grundfos UP Series pumps feature a canned rotor design in which the pump and rotor form an integral unit without a shaft seal to provide long life, excellent performance, and quiet operation. Internally lubricated bearings eliminate frequent lubrication. The UP Series' impeller is made out of corrosive-resistant, non-metallic material.