... wellhead assembled of gauge bull plug, tree cap,threaded nipple,top connetctor,valves,cross and spoolNB:2-9/16" 3-1 ... and overseas oil fields, it consists of casing head, casing spool,tubing spool,tubing head adapter,studded cross, threaded flanges,adapter spool ... of threaded nippe,solid bull plug,tree cap,cap flange,top connector, valves,cross and spool