Protects against sand and debrisSimply mount the Preliminary Filter between the Garden Pump Pressure Tank Unit or Electronic Pressure Pump and the Suction Hose. It effectively protects against impurities and is especially recommended for the pumping of media that contain sand. The filter can be washed. The Preliminary Filter has a 33.3 mm (G 1) mating thread and is suited for a water flow of up to 3000 l/h.