3/8-16 Serrated Flange Hex Lock Nuts Case Hardened HR15N 78/90 Black Zinc and Bake 1/4-20 while the 5 1/4-inch length

while the 5 1/4-inch length provides ample reach

The zinc coating protects the bolt from rust and other environmental factors

These bolts have a hex head for easy installation and removal

which means that the threads do not extend the full length of the screw

Its grade 5 rating indicates a tensile strength of 120

3/8-16 Serrated Flange Hex Lock Nuts Case Hardened HR15N 78/90 Black Zinc and Bake 1/4-20 while the 5 1/4-inch lengthThese 3 8 16 Serrated Flange Hex Lock Nuts are made of case hardened HR15N steel and have a black zinc and bake finish. They are designed to provide a secure and vibration resistant connection in a variety of applications. The serrated flange helps to prevent the nut from loosening, even under extreme vibration. These nuts are also RoHS compliant and meet the requirements of ASTM A563 Grade C.