40 Manufacture and forging of metal goods to the order and specification of others; metal heat treating services by means of gas furnaces and quenching or cooling methods using air, water, liquid polymer, and oil; machine shop services, namely, machining parts for others; welding services; custom manufacture of oilfield equipment, certified baskets, double wall environmental tanks, waste oil storage tanks, substructures, frac tanks, batch mixing tanks, mud systems, pressure vessels, drilling system components, subsea equipment, mud mats, manifolds, buoyancy cans, in-line sleds, mid-line sleds, tie-in sleds, high-pressure systems, landing pads and foundations, skids and skid-mounted equipment, custom manufacture and assembly of oil and gas equipment, namely, rotating head elements, annular packer elements, seal sleeves, bridge plugs, thread protectors, centralizers for others; custom manufacture and assembly of metal goods and machinery for others for use in the oil and gas industry, petrochemical and refining, transportation, military, power generation, and aerospace industries