Bolts, Hs Clip Bolt, Track bolt, Hex bolt.we can manufacture products basing on customers'drawing. Bolts:1. Surface treatment: Nuture, black, pot galvanizing, cold galvanizing, oil, parkerising etc.2. Grade: 4.6, 5.6, 8.8, 10.6 and12.93. Dia: from M16 to M604. Length: unrestricted5. Standards for railway products: T B, UIC , AREA, etc. standard components:GB,DIN,ASTM.BS,etc6. Package: according ...