This hydraulic filter element removes particulate contamination from the hydraulic oil before it circulates through the pump and control valves. It mounts in the filter housing on the return side of the hydraulic loop. A clogged element forces the bypass valve open, allowing unfiltered oil to pass downstream, which accelerates wear on the pump and actuator seals. The manufacturer machines the sealing surfaces to match the housing bore, ensuring the bypass valve cracks at the correct pressure differential. Replace the housing seal during installation and torque the cap to specification.