Used on upright Norton gearbox's, these stainless steel thin width spring washers fit under the blind nut on the front gearbox cover.
It is important to make sure they are fitted, as without them the blind headed shouldered nut fitted to the end cover (Item 0099) will scratch the gearbox cover and may 'bottom out' to the stufd before fully tightening the cover
When locked down, they also look identical to the original 'thin width' washers fitted under bevel casting (reduced head) nuts of SOHC/DOHC engines, so can be used there as well.
They are slightly slimmer than standard 5/16" spring washers. They also have the advantage that being a spring washer, if you have not got the perfect spanner for the rear bevel nuts (which are partly obscured), this spring washer should give you more chance of ensuring the rear nuts do not loosen fully off. Sold as pack of 20 here.
These washers are also standard fitment in the BS001 Bevel Stud/Nut set. (Note: we also sell normal width 5/16" washers for normal application - Item number 0509