Square Nut: 5/8"-11 Thread Size, Stainless Steel, 18-8, Plain, 35/64 in Ht, 1 in Wd, 18-8, 5 PKSquare Nut: 5 8" 11 Thread Size, Stainless Steel, 18 8, Plain, 35 64 in Ht, 1 in Wd, 18 8, pkg. of 5 Square nuts fit into square shaped openings, channels, or slots. They are primarily used in blind fastening situations where their flat sides can engage the mounting surface and prevent undesired rotation. Item 41JV54 Mfr. Model U51096. 062. 0001 Dimensional Standards ANSI ASME B18. 2. 2 Finish Plain Material Stainless Steel Material Grade Class 18 8