... : 4.8-12.9 grade Specification: Product NameBlack Plated Axle lock nut plating with blackBrandWDMaterialCarbon Steel (35#, 45#), Alloy steel (35crmo ... "-4" Length5mm-350mm Mechanical grade 4, 5, 6, 8, 9, 10, 12 grade Standard GB, BS, ANSI, JIS, DIN Surface treatment ... samples.2. Non-standard product is available. Black Plated Axle lock nut plating with black