STAUFF return-line filters made from aluminum, plastic or steel for line installation or tank mounting are often the only protection for a hydraulic system. They are suitable for operating pressures up to 25 bar (360 PSI) and are placed as working filters and the last element in the hydraulic circuit directly upstream or downstream of the hydraulic tank. There, they clean the entire returning hydraulic fluid before this is fed back into the tank. Line filters are used in the low-pressure range for high nominal flow rates up to 13,330 l/min (3,500 US GPM).