This part has been designed to allow our US1M 71" Carbon Fiber Mast (CF105) to fit into the mast tubes of the original Bob Sterne US1M Venom. The original masts for the Venom are no longer available and our US1M mast while stiffer then the Sterne original is slightly wider and does not fit into the mast tubes. This adapter is a solid 3d printed part in black PLA. The adapter has a recessed base to allow it to fit over the threaded rod and nut for the keel fin that is found in the middle tube of the original Venom.
For new project builds that will utilize our masts - we have available part# CF106 that is a rough cut 5" Carbon fiber Tube that can be used as the mast tubes for a new hull.