Plain Washer Flat Washer Type Standard Dimensional Standards DIN 433 Material Steel Material Grade/Class Grade 2 Finish Zinc Plated For Screw Size M18 Inside Diameter 19 mm Outside Diameter 30 mm Maximum Thickness 2.5 mm System of Measurement Metric Minimum Thickness 2.5 mm Maximum Temperature 302 Degrees F Minimum Temperature -58 Degrees F Pack Size Small Pack Package Quantity 100