3-piston alternating volumetric pumps for use on cleaning units and industrial systems. Hollow shaft version with flange F41 included for petrol & diesel engines using ø1″SAE J609a. Pump body and cover in die-cast aluminium alloy. Rear cover with oil drain outlet and oil sight glass. Cap with dipstick for oil level on body pump. Pistons driven by crank-connecting rod mechanism. Pump shaft in pressed high-strength steel. Oversize friction bearings. Connecting rods in bronze. One-piece ceramic pistons. Pump head in nickel-plated brass with valves cups in stainless steel. Double gasket sealing system. Intake and delivery valves have plugs for easier maintenance.