We have these steel tubes made for us to exacting O.E.M. standards and specifications. All choke tubes have the proper fiberglass insulation, fittings, rubber hose, and S-clip. Also includes cold air tube when applicable. 64-73 - 260, 289, 302, 2 BBL.64-66 - 260, 289-2, or 4 BBL.69 - 351W-2 BBL.