Locking plates engage a keyway in a shaft or adapter sleeve and are attached to the side face of the nut by two bolts secured with locking wire.
A locking plate consists of a plate, two hexagonal head bolts with drilled heads and lock wire to secure them
Spacers are the small parts inserted in-between the two bearings of your skate wheel axles. They take care of the coherence between the two bearings, in order to optimize the matching and synchronization of their rotation. The bearings lean on them when tightened.
The most common model is shown on the 3D diagram below (in blue): a floating collar spacer with an axle of 8 mm.
