The Serrated/Helix design creates air turbulence in the intake manifold. This turbulence increases the air pressure in the combustion chamber resulting in increased horsepower, torque, and improved throttle response. The Serrated/Helix combination design also reduces intake whistle that occurs with other helix only designs. All Silver Bullet Throttle Body Spacers are precision machined from 6061-T6 billet aluminum for lightweight, high strength, and perfect fit and finish. It is black anodized for a durable long-lasting finish. This premium wrapped coupling is constructed of high temperature silicone which meets or exceeds SAEJ20 Standards. This Silver Bullet throttle body spacer uses all factory mounting locations and a gasket ensuring a proper seal and a hassle-free installation.