Flat Washer Flat Washer Type Standard Material Alloy Steel Material Grade/Class Grade 2 Finish Plain For Screw Size M16 Inside Diameter 17.52 mm Outside Diameter 32 mm Maximum Thickness 3.1 mm System of Measurement Metric Minimum Thickness 3.1 mm Color Blue Pack Size Small Pack Rockwell Hardness RC38 RoHS Compliant Yes Package Quantity 5