This filter set includes the hydraulic oil filter and the engine oil filter required for the scheduled 50-hour service interval. The hydraulic filter captures particulate from the return line before fluid re-enters the reservoir, protecting downstream valves and actuators. The engine oil filter removes combustion byproducts and wear debris from the lubrication circuit. Replacing both filters at the same interval ensures the fluid systems are serviced together, preventing contamination from a neglected filter from affecting the other system.