... 3.Grade:4.8,8.8,10.9,12.9 4.Material:Q235,45#,40Cr ASTM DIN GB ... Standard High strength 12.9 bolt grades with large hexagon head for steel structures I. ... III. Usage:Supply to railway, highway, bridge, boiler with steel structure, industry workshop, high civil buildings, hoisting machinery ... and drawings of the products to our e-mail! V. Our strength on exporting: 1.Our company (Suzhou ...