Motorcraft FL-820-S Oil Filter Helps protect against engine wear by screening out abrasives, such as carbon, sand, dust and bits of metal before they can get into your oil Pressure-relief valves help minimize the chance of contaminated oil circulating back into the engine Pressure-relief valves also help maintain the supply of oil to the engine under extreme cold conditions or if the filter gets clogged Steel cases are ironed for a precise fit, fluted to ease removal and painted to resist rust Efficient filter media offers increased dirt-collecting capability and ability to capture more engine-harming particles Steel Cases Minimizes the chance of contaminated oil recirculating back Anti-Drain Back Valve Pressure Relief Valve Resists fatiguefailure