3" Velocity StackImpressive horsepower and torque gains on engines running modified and ported cylinder heads or intakes with larger throttle bodies Great performance part for racing and for those that want to head to the track on the weekend 3" tall billet aluminum for M8 throttle body bolt pattern 4" diameter opening with an internal taper down to 2. 4" ID matched to 62 mm throttle bodies Includes gasket and hardware Made in the USA Will require a custom breather