... flat washer without chamfer for screw up to property class 8.8 Product name Galvanized flat washers SpecificationM2-M40MaterialMild carbon steel, medium ... steel,copper,phosphorization, dacromet,cuprodine.Material grade A2,A4, 4.8,6.8,8.8,12.9Color Plain, blue plated, white plated, yellow plated ... flat washer without chamfer for screw up to property class 8.8