Carburetor SpacerOutside aluminum spacer is made to take a phenolic insert in the inside, based on your manifold needs.Made from an advanced phenolic thermoset plastic to withstand high manifold heat temps.Insulates and reduces the heat flow to carburetors, made to fit Holley, Carter, & Quadrajets.increase your power and performance with a carb spacer.Designed to fit the standard bolt patterns in Holley & Carter.Precision die-cast aluminum spacers come complete with all hardware needed.Universal Bolt Pattern4 Barrel carb type