"Fast changeover, even in the field. Pre-plumbed and pre-tested. Fits 4-bolt engine face plates. Bolts not included use existing bolts from old pump to install new pump. U.S.A. Max. PSI 3,500, Shaft Diameter in. 20mm, Application Pressure washer pump, GPM 4.5, HP 11 electric, 15 gas, Fuel Type Electric, gas. Pre-plumbed and pre-tested Fits 4-bolt motor face plates Belt drive"