... capable 3.Grade:4.8 ,6.8,8.8,9.8....... Bolt M10,Iron Bolt,Steel Bolts.1.What’s ... Copper,Aluminum are available.Carton steel is high quality iron,such as 1022,1018,1010,1008,1015...Medium carbon ... not break when you tighten the fasteners by wrench ,key ,bit and spanner.When head become thicker,and then ... is convenient to tighten the fasteners by wrench,,bit,key etc.3.The scrows are also much deeper than ...