... 8.8,9.8... Double End Bolt,Special Head Bolt,Bolt Maker ,M6 Bolt Dimensions1.What’s the specification of ... "thread are available.Head typesHexagon head,Mushroom head,Pan head,Countersunk head,Bugle head,Oval head,Hex flange head,Round head,Ball head,Button head...Socket typesPhillip type, ... ,is higher than other Carbon Steel .2.Fasteners' Head is much thicker than some other manufacturers ,it is strong ...