Designed to enable the lower section of 14 mm diameter mast tube to be removed from the upper section of 12 mm diameter. It is a slim tube that is locked onto the lower end of the 12 mm diameter carbon tube 100 mm above the lower end. Use cyanoacrylate glue for this purpose and ensure it is properly cured before it is used. When assembled the joiner fits neatly over the top of the 14 mm section and protects it from splitting.
This should be a real bonus for those occasions where you need to make rigs pack down into a much smaller space and still retain the strength of the joins.
