Lock Washer Lock Washer Type External Tooth Lock Finish Zinc Plated Material Steel For Screw Size M5 Inside Diameter 5.1 mm Outside Diameter 9 mm Maximum Thickness 0.5 mm Dimensional Standards DIN 6798 A Material Grade/Class Not Graded Pack Size Small Pack Rockwell Hardness C38 to C46 System of Measurement Metric Package Quantity 100