7 Power transmissions for agricultural, industrial and commercial machines, consisting of gear boxes, gear drives, power drive lines and power trains; parts of earth augers, namely, power auger drives for excavation; disk mower boxes comprised primarily of gearboxes for power lawn mowers in the nature of disk mowers and also containing machine parts, namely, disk mower cutting heads and drive shafts; rotary tables; gearboxes, gear drives being machine parts, and gear drive lines for agricultural, industrial and commercial machines, and structural parts therefor, namely, loose gears, drive line shields, and drive line couplers; planetary drive gearboxes for agricultural and industrial equipment; structural parts of agricultural, industrial, and commercial machines, namely, mechanically and electrically powered drive lines and parts therefor, namely, drive line safety shields and guards; gears for machines, namely, gears for drive trains and gearboxes; low-speed high-torque orbital motors, other than for land vehicles; gear motors not for land vehicles; spring-applied pressure release brakes for machines; planetary drive systems, namely, planetary gear motors; gearboxes other than for land vehicles, namely, right angle drive gearboxes; hydraulic drive systems, namely, hydraulic motors, for agricultural, industrial, and commercial machines