Feature● Extends length of intake mixture column to improve air/fuel distribution CNC machined from 6061-T6 billet aluminum to extremely accurate specifications Billet aluminum eliminates porosity and improves engine appearance 4500 Series Holley bolt patterns to fit a variety of carburetors 4500 Series (Dominator) Spacer is 1" thick with open plenum Open designs increase plenum volume for improved high rpm power Gaskets are not included *Not legal for sale or use on pollution-controlled vehiclesDescription CARBURETOR SPACER, 1 IN., BILLET ALUMINUM