Rough Country's Throttle Body Spacer helps you get the most out of your 99-06 GM 1500. Engineered with a Spiraling Helix design, our durable, aluminum spacer forces incoming air into a high velocity vortex that aids in a more powerful and efficient fuel combustion process. This process offers improved torque performance and increased fuel economy. Includes an OEM style rubber O-Ring Gasket, superior to paper gaskets found in inferior kits. Best of all, this modification is easy to install using a 100% bolt-on installation process that can be attached in no time! Works with multiple engine sizes: 4.8L/5.3L/6.0L.