... :4.8 ,6.8,8.8..... Semi tubular rivet,stainless steel rivet,tube rivet . 1.What’s the specification of our Products ? MaterialCarbon steel,Stainless steel,Alloy steel,Copper ... typeHexagon head,Mushroom head,Pan head,Countersunk head,Bugle head,Oval head,Hex flange head,Round head,Ball head,Button head ...