This set contains five replacement spring washers (lock rings) and will fit all Pitlock wheel skewers and seat skewers. If you’re using Pitlock’s solid axle nuts though, you’ll need the larger solid axle stepped washers.
The spring washer is part of the Pitlock closure and anchors its springs in the notches of the coded nut. This is how the closure is locked. To open the Pitlock closure, the Pitlock key has to be pressed into the closure; by pressing down the springs, the coded nut is unlocked.
Spring washers are wearable parts, and should be replaced after extended use, or frequent wheel removals / installations.