Lock Washer, Lock Washer Type External Tooth Lock, Finish Plain, Material Stainless Steel, For Screw Size M5, Inside Diameter 5.3 mm, Outside Diameter 10 mm, Maximum Thickness 0.6 mm, Dimensional Standards DIN 6798, Material Grade/Class 18-8, Pack Size Small Pack, System of Measurement Metric, Package Quantity 50 Closed Perimeter Serrated External Tooth Metric Lock Washers have angled teeth that absorb vibration and maintain fastener tension to help prevent loosening. Thickness is a range.