we are a manufacturer of washers. 1)M10-M52 2)steel, ss304,316,etc. 3) ... ,etc. 4)din6796,DIN6798,DIN6797,din125 Type: flat washer,plain washer,round washer,spring washer, square washer, etc.STANDARD: DIN434, DIN435, NON-STANDARDSIZE: M9-M30MATERIAL ...