The 520002 Replacement Pressure Washer Pump has stainless steel pistons for improved seal life and features a stainless steel integrated unloader with our easy-start system with a Max PSI of 3400PSI at 2.5GPM Easy Installation: This replacement pump features a garden hose inlet and threaded M22 connection high pressure hose outlet with a 3/4 hollow shaft 3/16 keyed drive syste. The SAE standard bolt pattern that fits most* gas-powered pressure washers. Get your machine back in action as quickly as possible. (*Check your pressure washer's inlet and outlet orientation to ensure compatibility) Extended durability: A Thermal Relief Valve (TRV) protects the pump from overheating while in bypass mode. The TRV releases small amounts of hot water and intakes cooler water to prevent overheating and extend the life of the pump Extend the life of your pressure washer: Save money by replacing your pump instead of buying a whole new power washer. This easy-to-install kit is great for power washers that can support 3400 PSI at 2.5 GPM to wash walls, fences, sidewalks, vehicles, and more The 520002 OEM Technologies Axial Cam Pump is highly efficient and minimizes engine load. This easy-to-install pump replacement kit is for gas pressure washers* with a horizontal engine and a 3/4″ diameter shaft. The 520002 Replacement Pressure Washer Pump has stainless steel pistons for improved seal life and features a stainless steel integrated unloader with our easy-start system. 3/4″ diameter shaft 3400 PSI at 2.5 GPM Horizontal mount *Check your pressure washer’s inlet and outlet orientation to ensure compatibility