High Collar Lock Washers
Extra Thick Split Ring Lock Washers
High Collar lock washers are designed to fit under the head of a socket cap screw. A split washer or a spring lock washer is a ring split at one point and bent into a helical shape. This causes the washer to exert a spring force between the fastener's head and the substrate. Applicable standards are ASME B18.21.1, DIN 127B, and United States Military Standard NASM 35338 (formerly MS 35338 and AN-935).