... 3.Grade:4.8 ,6.8,8.8.... Aluminum Fastener,Non standard Fasteners,Aluminum Fasteners.1.What’s the specification of our Products ... ? MaterialCarbon steel,Stainless steel,Alloy steel,Copper,Aluminum are available.Carton steel is high quality iron,such as 1022,1018,1010,1008,1015 ...