Small O.D. Flat Washer, Flat Washer Type Standard, Dimensional Standards DIN 433, Material Steel, Material Grade/Class Case Hardened, Finish Zinc-Plated, For Screw Size M18, Inside Diameter 19.33 mm, Outside Diameter 30 mm, Maximum Thickness 2.7 mm, System of Measurement Metric, Minimum Thickness 2.3 mm, Material Quality Standards 140-250 HV10, Maximum Temperature 302 Degrees F, Minimum Temperature -58 Degrees F, Pack Size Small Pack, Package Quantity 100