The category covers hex and flange nuts, nylon-insert lock nuts, flat and wave washers, sealing washers, snap and retaining rings, and the small retainers that keep a pin or a cable end located.
Roughly 3,400 parts are listed across nuts, washers and rings and retainers, in GM, Ford, Mopar and ACDelco numbers. Many of the sealing washers here are single-use items on the assemblies they belong to — transmission pan washers, oil drain washers and A/C line seals — and reusing one is the usual cause of a leak after a repair.
Match the thread size and pitch to the fastener, and match the type to the joint: a lock nut and a plain nut are not substitutes on a suspension or steering component, and a wave washer is there to maintain preload, not just to spread load. Where a listing is a pack, the pack quantity is stated in the title, because a single retainer is rarely what a repair actually needs.
