The Nut,hex.,8mm is the lowest priced item on this Swingarm / Chain Case - Xl500s 79-81 schematic.
This schematic depicts all components used in the Xl500s 1981 (b) Usa Swingarm / Chain Case - Xl500s 79-81 partslist.
Some items from this specific schematic: Nipple,grease, Washer, Thrust, Cap, Dust Seal, Case,drive Chain.