Modern Confluence Rudders have a plastic axle that the rudder blade rotates on to lower and raise the blade from the water. This Axle comprises 2 plastic sections and a self tapping screw. It is possible to over tighten the screw and strip the insert hole so the rudder axle is no longer held in place securely.
Normally this is done accidently as part of incorrect servicing (i.e. trying to tighten or loosen the rudder movement, not realising that screw does not effect the ease or difficulty of the rotation/flip of the rudder blade and screwing to hard)
This is a replacement piece for that one part of the plastic axle and does not include the plastic sheave, self tapping screw or the other (female) half of the axle. If you have accidently caused the screw to not grip the plastic this is a simple fix.
See pictures for details.
The complete axle Kit which includes the other half of the axle, the sheaves (or pulley wheels) and the screw is part 9801060.