Lock Washer, Finish Zinc Plated, Material Steel, For Screw Size 3/8 in, Inside Diameter 0.394 in, Outside Diameter 0.654 in, Color Silver, Material Grade/Class Not Graded, Pack Size Small Pack, Rockwell Hardness C46, Thickness Tolerance +/-0.28 mm, Package Quantity 200 This NORD-LOCK(R) Carbon Steel Lock Washer compresses as the fastener is tightened to securely lock bolt or screw heads into place to prevent counterclockwise rotation from vibration.
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