Flat Washer, Flat Washer Type Standard, Dimensional Standards DIN 125-1A, Material Steel, Material Grade/Class Grade 5, Finish Zinc Yellow, For Screw Size M20, Inside Diameter 21 mm, Outside Diameter 37 mm, Maximum Thickness 3 mm, System of Measurement Metric, Minimum Thickness 3 mm, Pack Size Small Pack, Package Quantity 10