aFe Power Momentum GT 54-74104 GM Silverado/Sierra Performance Intake System (Oiled, 5-Layer Filter) Outflows the factory intake by up to 35% . Produces an additional 12 max horsepower and 15 lbs. x ft. torque 5-Layer progressively finer oiled, washable cotton gauze media allows maximum airflow for maximum power Smooth one-piece sealed housing with auxiliary air scoop and built-in sight window A urethane plug is also included if you wish to completely seal the air box This product is 50-state legal (CARB E.O Number D-550-13)