Helical spring lock washers. The helical spring lock washers covered by this standard are intended for general industrial application. They have the function of: (1) providing greater bolt tension per unit of applied torque for tighter assemblies; (2) providing hardened bearing surfaces to create more uniform torque control; (3) providing uniform load distribution through controlled radii--section-- cut-off; and (4) providing protection against looseness resulting from vibration and corrosion.

Tooth lock washers. The tooth lock washers in this standard are intended for general industrial application. They serve to promote the retention of fasteners, such as bolts, screws and nuts, to the component parts of an assembly by increasing friction between the fasteners and the assembly and by providing spring takeup.