https://www.fastenerdata.co.uk/fasteners/washers/flat/stainless-steel-flat-washer.html
Fastenerdata - Stainless Steel Flat Washer - Fastener Specifications
Stainless Steel Flat Washer are available in metric to din125, bs4320 and american specifications, there is also a full range of inch stainless steel washers.
stainless steel flat washerfastenerdataspecifications