M3, M4, M5, M6, M8. M5,M6,M8,M10 A2. Nylon Flat Washers. M4,M5,M6,M8 A2 Stainless Steel. M4, M5, M6, M8mm. M2.5,3,4,5,6,8,10,12,14,16,18,20. Stated sizes are the bolt size which the washers fit, hence the hole sizes are a little larger to allow clearance.
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