The serrated/helix 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 serrated/helix 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. Its black anodized finish gives a stealthy look. Adding a Silver Bullet Throttle Body spacer lengthens the intake track which helps increase intake air speed, performance and improve throttle response. This Silver Bullet throttle body spacer uses all factory mounting locations, making for a hassle-free installation. A supplied gasket provides a perfect seal. Silver Bullet Throttle Body Spacer Kit GM Colorado/Canyon 04-06 L5-3.5L/07-12 L5-3.7L GM Colorado/Canyon 04-06 L5-3.5L/07-12 L5-3.7L