... 8 ,6.8,8.8,9.8.... Copper Bolts,Copper Bolt,Brass Bolts.1.What’s the specification ... steel,Stainless steel,Alloy steel,Copper,Aluminum are available.Carton steel is high quality iron,such as 1022, ... is SS201,202,302,304,316...copper is shiny brass , pure copper,such as H62,H65,H68...Aluminum ... but is reasonable for products,it will spend high control force from material till products reach in ...