This is a set of Stainless Steel swinging arm nuts and washers. They will fit all tripple and early 750 models (not Zane twins). The nuts are nylock so will not come loose and the washers are machined from solid bar stock. The original parts numbers are 30531283 x 2 and 33114140 x 2, these items will outlast the rest of the machine. All stainless parts MUST be assembled with copaslip.