ojperformance.com VS.

primusracingparts.com

Steel Heavy-Vibration-Resistant Spring Lock Washers: for 5/16" and M8 Socket head screws. 0.331" ID, 0.512" OD. Thickness: 0.031" Overall Height: 0.055" Serration Location: Top and Bottom. Hardness: Rockwell C40 Lock Washer Type: Spring Material: Steel Performance: Heavy Vibration Resistant, Reusable Use with Suspension Clevis' such as 90D0028, 90D0029, & 90D0038. Sold individually. Stop socket head screws from wiggling loose on equipment with constant, vigorous vibration, such as engines, turbines, and generators. These washers have a small diameter to fit under screws with narrow heads. Similar to a spring, they flatten under pressure to add tension between mating surfaces. As long as the washers aren't deformed or otherwise damaged, you can reuse them indefinitely without losing locking strength. Also known as conical washers and Belleville washers. Stack multiple washers in the same direction to double or triple how much weight they can bear. Stack washers in opposite directions for better deflection, which means they compress further and withstand more shock and movement without loosening.