Clutches and apparatus for power transmission, other than for land vehicles; valves, namely, ball valves being parts of machines, butterfly valves being parts of machines, angle valves being parts of machine, check valves being parts of machine; dosing valves, being parts of machines; pump control valves; back pressure valves, being parts of machines; valves for and being parts of pumps; control valves for regulating the flow of gases and liquids, being parts of machines; couplings for machin...