The serratedhelix design creates air turbulence in the intake manifold. This turbulence increases the air pressure in the combustion chamber, resulting in increased performance and improved throttle response. The serratedhelix combination design also reduces intake whistle that occurs with helix - only designs (US PAT 07055513). This Silver Bullet throttle body spacer is precision machined from 6061 - T6 billet aluminum for lightweight, high strength, and perfect fit and finish. It features a black anodized finish. This Silver Bullet throttle body spacer uses all factory mounting locations, making for a hassle - free installation. A supplied gasket provides a perfect seal. An aluminum tube and coupling are included in the kit to guarantee a perfect fitment with the factory air intake system.