Electric compressors; heat exchangers, namely, engine parts other than for land vehicles; pumps for machines used in aeronautical and space industries, fluid pumps for machines used in aeronautical and space industries, valves for fluids, hydrazine propellers, bipropellant propellers and catalysis-enhanced propellers, all for machines; couplings for machines, not for land vehicles, transmission and propulsion units not for land vehicles, namely, power transmissions and gearing for machines, e...