The Unifiber 12 mm barrel insert is a threaded insert used to secure a windsurfing fin. Installed in the fin head, it provides a threaded socket for an M6 screw used to attach the fin to the board. It is suitable for Powerbox, Tuttlebox and Deep Tuttlebox fins designed for a 12 mm diameter insert.

It is a useful service part if the original barrel insert is lost or its thread becomes worn. Keeping a spare insert in your windsurfing repair kit is also a practical option when travelling.

Choosing the correct size

Before purchasing, check the diameter and length of the insert being replaced as well as the thread of the mounting screw. The 12 mm version requires a matching opening in the fin head and is not interchangeable with the 9 mm barrel insert.