Hexagon Nut Retainer - M6
Nylon Nut Retainer
Nut retainer used to secure head of a rudder pivot bolt on a Seasure Rudder stock.
(used for the kSail/Seasure Firefly Rudder Stock too)
For Fireflies, you may be interested in the kSail Pivot Bolt Upgrade to the Genesis/Rondar Rudder Stock