1/4-20 Serrated Flange Hex Lock Nuts Case Hardened HR15N 78/90 Black Zinc and Bake M5 while the 3/4-inch length ensures

while the 3/4-inch length ensures a firm hold

The square head prevents the bolt from turning when it is tightened

The hexagonal head allows for easy installation with a standard wrench or socket

This 1/2-13 x 1 3/4 Hex Head Flange Non Serrated Frame Bolt is made of high-strength steel and features a black phosphate finish for corrosion resistance

meaning they do not have a coating or finish

1/4-20 Serrated Flange Hex Lock Nuts Case Hardened HR15N 78/90 Black Zinc and Bake M5 while the 3/4-inch length ensuresThese 1 4 20 Serrated Flange Hex Lock Nuts are made of case hardened HR15N steel and feature a black zinc and bake finish. They have a serrated flange that helps to prevent loosening and a hex head for easy installation. These lock nuts are ideal for use in a variety of applications, including automotive, construction, and manufacturing. They meet the specifications of ASTM A563 Grade C and are RoHS compliant.