UNC Hexagon Nuts 1/2 1/4 3/4 3/8 5/16 5/8 7/16 4# 6# 8# 10# 12# 304 Stainless Steel US Standard American Form Hex Nut
https://www.vogueparade.com/shopping/EN/42/1/1005003456003843/unc-hexagon-nuts-12-14-34-38-516-58-716-4-6-8-10-12-304-stainless-steel-us-standard-american-form-hex-nut//