Filtration is essential to the health and longevity of your hydraulic system. Harken recommends the 40-micron suction/return filter between the reservoir and the pump as well as an extremely fine 3-micron filter between the pump and the valves. The 40-micron filter has an anodized aluminum body with a removable, cleanable, and replaceable sintered bronze element. The high pressure 3-micron filter is made from electropolished 17-4 PH stainless or titanium. It has a replaceable paper element and can handle pressures up to 10,000 psi. -4SAE ports allow the high-pressure filter to accept any combination of fittings and adapters.