Hypalon

A synthetic rubber (and its modern CSM equivalents) used for RIB collar tubes; UV- and chemical-resistant and the default for an exposed yacht tender.

Hypalon is the synthetic rubber, now usually supplied as the chemically similar CSM, used to build the inflatable collar tubes on a RIB tender. It is UV- and chemical-resistant and lasts 10 to 15 years in Mediterranean use, which is why it is the default specification for a tender that lives exposed alongside the yacht.

The alternative, PVC, is cheaper but degrades faster (5 to 8 years) and is only appropriate for a garaged, limited-use boat. The best RIB tenders guide covers the trade-off in full.