Spectre Performance HPR9891 Universal Clamp-On Air Filter: Round Tapered; 6 in (152 mm) Flange ID; 8.5 in (216 mm) Height; 7.719 in (196 mm) Base; 5.125 in (130 mm) Top Engineered for increased flow and greater performance Factory pre-oiled and ready to use Quality materials used throughout including synthetic media, urethane, and steel mesh Use P/N HPR4820 Accucharge kit to clean and re-oil the filter Use with a velocity stack to fit 2-1/2 (9601), 3 (9602), 3-1/2 (9603), or 4 (9604) intake tubing