... Co.,Ltd is one of the top level wellhead christmas tree manufacturers and suppliers,Website:http://www.zztopdownhole.com, ... 6A -Consist of casing head, tubing head and Christmas tree -Applicable to all the casing and tubing programs and ... 1/16, 2-9/16, 3-1/16(3-1/8), 4-1/16 Pass-by bore (in) 2-1/16, 2-9/16, 3-1/16(3-1 ... /8), 4-1 ...