1/4-20 Serrated Flange Hex Lock Nuts, Stainless Steel 18-8 (304), Black Oxide…
Product Specification Flange Nuts have flat and serrated designs designed to act as an integrated, non-spinning washer, eliminating the need for a separate washer. Serrated flange nuts are fabricated with a built in serrated washer that resist loosening due to vibration.