k n oliefilter arctic cat kn 621K&N Delivers a Premium Oil Filter which is Built with a synthetic media designed to withstand the high concentrates of synthetic racing oils, a large filter media provides high flow rates and outstanding oil filtration to keep your motor rummot Higher Flow Rates Associated with Synthetic and Synthetic Blended Oils, 17 mm Hex Nut (Pre Drilled for Safety Wire Security) Allows Easy On, Wrench off Removal, Uniform Pleated Synthetic Filter Media Turvides