Skunk2's all - new B Series 90mm adapter now offers B - Series enthusiasts even more flexibility. Manufactured out of 6061 - T6 billet aluminum, B - Series throttle bodys can be bolted on to the new Ultra Race Series intake manifold. Enthusiasts now have a few options for throttle bodies. Each unique, CNC - machined and hard - anodized throttle body adapter features a 74mm opening, recessed holes for easy adaptation, and all necessary mounting hardware is included with each adapter, making for an easy installation.