... high tensile nut bolts: 1. Spec.: DIN,JIS,ASTM,GB 2. Surface: black 3. Grade:4.8,8.8 ... 12.9 4. Material: Q235,45#,40Cr ASTM DIN GB Rail high tensile nut bolts with large hexagon head ... JIS B 1186, ASTM A325, ASTM A490, GB/T 1228, GB/T 1229, GB/T 1230 III. Usage:Supply to railway, highway ... used. We exported to world markets, such as U.S.A., Canada, Cuba, Germany, Japan, Singapore, Malaysia and Africa ...