Spacers are made from heat-treated cast alum. and will work with most all 4150 type carburetors. Spacers are drilled with thru holes on the manifold side and drilled and tapped 5/16-18 on the carburetor side. Hole thru the center measures 3.625" x 3.625". Finish is satin aluminum and spacers are sold each.
Buyer will need to purchase gaskets and mounting hardware separate.