The BERTOLINI Piston Pump is high quality! 1 Forged brass head providing great mechanical strength. The 8 bolts that lock the head onto the crankcase, are designed to endure higher pressure and even overpressures, ultimately reducing the risk from any unloader malfunctions. 2 Unique design of valve caps with recessed O-rings. The thread doesn’t come in contact with water under pressure, therefore eliminating the risk of head failure. Also eliminated the risk of valve caps loosening, even without the use of Loctite®. Torque wrench settings are reduced. 3 Rapid action, mirror finish stainless steel AISI 316 check valves prevent corrosion and enhance high fluid dynamic efficiency, easy access for maintenance and repairs. 4 New plunger rod to reduce the negative areas, therefore to increase the pump volumetric efficiency. Tungsten carbide coated to ensure maximum resistance to wear. 5 Exclusive double “U” self-lubricating packing seals in elastomer, designed to prevent water from contaminating the oil in the crankcase. This gives you years of leak-free operation. 6 Oversized special bronze alloy connecting rods (one piece unit) for maximum strength and easier lubrication. 7 Premium oversized bearings for extended life even under extreme working conditions. 8 Die-cast aluminium crankcase with an increased number of cooling fins on the housing.