Does anyone really like those white washers that come with 3PDT footswitches? We certainly don't, so here's a much neater solution
With a much smaller outside diameter than the white washers, these barely extend outside the nut, so have much less of a visual impact on your enclosure.
They are slightly thicker, but no biggy. It just means less exposed thread.
Dimensions of original white washers in brackets.
Inside diameter: 12mm (12mm)
Outside Diameter: 16mm (19mm)
Thickness: 2.8mm (1.2mm)