7 Metalworking machines and tools; motors, other than for land vehicles; motors, electric, other than for land vehicles; non-electric prime movers not for land vehicles and parts thereof, namely, cylinder heads, cylinder blocks, hub and drum assemblies, hub and rotor assemblies, differential cage, differential carriers, exhaust manifolds, brackets, valve controls, motor covers, link brackets, axle housings, differential carriers, carrier planets, engine assemblies, rocker arms, flywheels, ring gears, drive plates; mechanical couplings and transmissions, other than for land vehicles; machine elements not for land vehicles, namely, cylinder heads, cylinder blocks, hub and drum assemblies, hub and rotor assemblies, differential cage, differential carriers, exhaust manifolds, brackets, valve controls, motor covers, link brackets, axle housings, differential carriers, carrier planets, engine assemblies, rocker arms, flywheels, ring gears, drive plates; AC motors and DC motors not including those for land vehicles but including components for any AC motors and DC motors; AC generators being alternators; DC generators; shafts, axles or spindles not for land vehicles; shaft couplings or connectors being machine elements not for land vehicles; power transmissions and gearing for machines not for land vehicles; valves being machine elements not for land vehicles; engines, other than for land vehicles; parts of engines, namely, bearings being machine elements not for land vehicles; bearings being machine elements not for land vehicles; ball-bearings being machine elements not for land vehicles; Mechanical elements for land vehicles, namely, engine parts including rocker arms, flywheels, ring gears and drive plates