... Standard:API 6A,ISO9001 Application:Wellhead component Type:Octagonal,Oval and Groo Well head accessories API 6A gasket rings is widely used ... ,flange,etc. StandardApplicationshapeAPI 6A,ISO 90012000,ISO9001 2008,ANSI etccasing head,flange, gate valve, oil&gas industry, oil christmas tree, ... in API 6A products as below:1) Wellheads (casing/tubing head, crosses ,flange adapter,etc)2) Valve (FC/FLS gate ...