The tube is made of brass.

You need to provide an external scavenge tube for the late model carburetor to be in compliance with Coast Guard regulations. Moyer Marine (www.moyermarine.com) has them.

On late model engines, these scavenge tubes are installed between the 1/8" pipe-threaded hole in the bottom of the intake throat of the carburetor and a 1/8" pipe-threaded hole in the intake manifold, just aft of the carburetor mounting flange. If you do not have the capability to drill and tap such a hole in your early model manifold, you can order a spacer kit from Moyer Marine which installs between the manifold flange and the carburetor. These spacers have a 1/8" hole pre-drilled and tapped to receive the upper end of the scavenge tube.

Bill