structures and system components of metal for use in the drilling and production of oil and gas wells, namely, wellheads, tubing hangers, tree caps, manifolds, risers, running tools and landing strings; manually operated metal flow control valves and parts thereof
Metal Goodsparts of machines for oil and gas well drilling and production, namely, christmas trees, wellheads, tubing hangers, tree caps, manifolds, risers, and flow control valves
Machineryoil well christmas trees in the nature of an assembly of valves, spools, and fittings for controlling the flow of fluid into and out of a subterranean well; control valves for regulating the flow of fluids; electric controls for operating oil and gas well drilling and production systems and system components; electric valve actuators; electric control devices for oil and gas well drilling and production systems and system components
Electrical and Scientific Apparatus