We are China Wujiang City ZhangYu Metal Products Co., Ltd , specialized in all kinds of standard and non-standard lock washers. We have passed the ISO system authentication,and is applying theTS16949 system authentication.So we are competitive in both price and quality.If you need ,please do not hesitate to contact me,I will give you the lowest quotation. Standard: DIN, BS, GB, ISO, NI, NFE, JIS, AS Size: M3-- Material: Steel, Stainless steel , Copper, Aluminium, Stannum and so on Surface: Plain, Zinc, H.D.G, Phosphorus and so on