... 3)Material:Steel,Stainless steel 4)Finish:Zinc,Black,Nickel,Tin Flat Washer1) Standard: DIN, BS, IFI, JIS, ISO,GB,ANSI ... , etc.4) Finish: Zinc Clear, Zinc Yellow, Black, Nickel-plating, Tin-plating, Chrome- plating, Dacromet,Mechanical Galvanizing, Hot-dip Galvanizing.etc.5) Shape: round ...