Husqvarna 521580001  Oil Filter

The purpose of the Oil Filter is to allow a constant supply of Oil into the engine while stopping any dust, dirt, bits of grass, or other small debris from passing through and potentially causing damage to the cylinder and piston. If the Oil Filter is clogged, it can prevent proper Oil flow and cause the engine to lose power. Home users often replace their Oil filter during their annual tune-up. Operating with a clean Oil Filter will improve the performance and prolong the life of your equipment.