This retainer is made from .049" thick 300 series stainless steel and is 14 mm in length. It fits all of our right side replacement inserts that are compatible with a Shimano 12 mm skewer. The retainer holds the Shimano skewer nut captive and includes a M4 x 8 mm zinc-plated steel button head cap screw to secure it. It is only applicable to the Shimano skewer.
The nine notches in the retainer index the notches on the nut. This allows the closed position of the skewer to be adjusted every 40 degress for optimal location. If none of these positions work, the retainer can be flipped over to utilize nine more positions that are 20 degrees out of phase from the original positions.
Item sold as two piece set.