... .,Ltd is one of the top level casing and tubing head manufacturers and suppliers,Website:http://www.zztopdownhole.com, with professional ... factory, we are able to produce API and oilfield casing head, tubing head, casing spool, tubing spool, tubing hanger, casing ... versatile straight-bore, the casing head and casing spool can be equipped with mandrel hanger and slip hanger, to handle any ...