7 Machines and machine tools for the cutting and for mixing of materials; electric and hydraulic pumps, fuel injectors, engines not for land vehicles for machine operation, transmission gears for machines, workover equipment, namely, drilling machines; mudding equipment, namely, drilling mids for use in oil well drilling, mud dredging machines; cement mixers, centrifugal pumps,recirculating mixing machines, electric drills, electric motors for machines, packing machines, machines, namely, liner hangers and landing nipples used in well completions, hydraulic valves for pumps, pneumatic valves for pumps, machines, namely, wireline formation tester and wireline cutters for use in well workover and intervention, machines, namely, rotary sidewall coring machines for use in the field of oil drilling, machines, namely, material blenders, sand feeders and conveyors, cementing, fracturing and acidizing tools all for use in the field of oil drilling; power tools, namely, retainers, plugs, fluid injectors, and gun perforators; hydraulic valve actuators, couplings for machines; machine parts, namely, high pressure jetting nozzles which are parts of power-operated sprayers; machines, namely, oil well cement dump bailers; machines, namely, perforators for use in perforating oil and gas wells; machines, namely, combination fluid sampler and filtration units for use in oil-well drilling; mechanically power-operated well intervention tool, namely, a wireline retrievable well bore bridge plug for use in oil and gas well exploration and production; drilling rigs; machines for use in cementing and treatment of wells in the form of cementing units, cementing plugs, water control apparatus, sand control apparatus, scale control apparatus and foam application apparatus, liquid additive installations, namely, mixers and blenders for use in the field of oil drilling; machinery used for transporting and metering bulk material used for the purpose of oil drilling; combination machines for use in perforating, downhole casing repairing, packing, bridge plug and cement retainer setting, sand setting and consolidating, casing and tubing cutting and for pipe and apparatus recovery, all the aforesaid for use in well completion; electric pumps, pump control valves; machines used for the purpose of free point indicating in the field of oil drilling; industrial cleaning apparatus machines for cleaning pipes, boilers, heaters, coolers, condensers, evaporators, exchangers and nuclear steam generating equipment; motors and engines not for land vehicles; machine coupling and transmission components not for land vehicles