... the specification of our Products ? MaterialsCarbon steel,Stainless steel,Alloy steel,Copper,Aluminum are available.Carton steel is high quality iron,such as 1022 ... not break when you tighten the fasteners by wrench ,key ,bit and spanner.When head become thicker,and then the socket ... manufacturers,it is convenient to tighten the fasteners by wrench,,bit,key etc.3.The scrows are also much deeper than ...