7 OIL AND/OR GAS WELL PRODUCTION MACHINERY, NAMELY, WELLHEADS, DUAL WELLHEADS, ELECTRIC FEED THRU WELLHEADS; PARTS OF OILFIELD AND/OR GAS FIELD WELLHEAD MACHINES, NAMELY, CASING HEADS, CASING HEAD SPOOLS, CASING HANGERS, TUBING HEADS, TUBING HEAD SPOOLS, TUBING HEAD ADAPTERS, TUBING HANGERS, DUAL COMPLETION TUBING HANGERS, SECONDARY MECHANICAL SEALS, WELLHEAD FLANGES, CROSSES AND TEES, STUFFING BOXES, ROD CLAMPS, TUBING ROTATORS, BORE VALVES, FLUID AND GAS FLOW VALVES, FLUID AND GAS FLOW CHOKES, TENSION SET PACKERS, RING SEAL PACKERS, FRACTURING AND FLOW BACK TREES, BOWL PROTECTORS, WEAR BUSHINGS, TEST PLUGS, BACK PRESSURE VALVES, VALVE NIPPLES, LUBRICATOR ADAPTER CAPS AND LUBRICATORS, AND ANY COMBINATION OF THE AFOREMENTIONED GOODS SOLD AS A UNIT