Sierra high-efficiency oil filters meet or exceed OEM specifications for marine use, unlike conventional auto oil filters. Available for gasoline inboard and 4-stroke outboard applications, each filter features a high pleat count to increase capacity and improve efficiency. Heavy-walled painted canisters offer corrosion resistance to the exterior; interior walls are epoxy coated for additional corrosion protection. Individual filters are shrink-wrapped for rust protection when spares are stored onboard. Some models utilize anti-drainback valves, where applicable.