8.8,10.9,12.9 grade of Track bolt,plow bolt,segment bolt and nut We ... earthmoving fastener,all of our fastener are made by high grade alloy steel,the surface hardness can reach HRC36-42,tensile ... strength is 170,000 P.S.I. There are 10.9,12.9 class of ... ,we will reply you as soon as possible. 12.9 grade of earthmoving bolt and nut