Velocity Stack with 3" outlet for Cold Air / Short Ram Intake Kit Made of ABS plastic Works with any aftermarket air filter with 4.5" inlet 3" outlet This velocity stack is designed to optimize and maximize the entry of air flow entering the vehicle's induction system. The low velocity air flow taken thru the air filter is turned into a smooth and high velocity intake charge. High velocity intake equals more horsepower output. Great for custom DIY shortram air intake, ram air intake or cold air intake kit.