4″ Blackmer X4 pump, very nice rebuild. Depending on the viscosity of what your pumping this beast can move up to 400GPM. At higher viscosity/longer distance, the XL4 will reliably pump about 250 to 350GPM. Even though this is an older model, all parts are still available, and after we rebuilt this unit you should not need anything for many years of service. NEW mechanical seals, vanes, push rods, relief spring & gaskets/o rings.