Couplings for machines, namely, internal and external splines; shaft couplings for machines, namely, internal and external splines; internal and external splines for transmissions and transmission parts used in machines except for land vehicles; internal and external splines for machines except for land vehicles; internal and external splines for wheel, track and drum drives used in machines except for land vehicles; internal and external splines for shaft output drives used in machines except for land vehicles; internal and external splines for spindle output drives used in machines except for land vehicles; internal and external splines for compact and integrated drives used in machines except for land vehicles; internal and external splines for jacking drives used in machines except for land vehicles; internal and external splines for hoist drives used in machines except for land vehicles; internal and external splines for winch drives used in machines except for land vehicles; internal and external splines for electric drives used in machines except for land vehicles; internal and external splines for compact double and triple reduction drives used in machines except for land vehicles; internal and external splines for yaw drives, main drives, and pitch drives used in machines, namely, for wind turbines; internal and external splines for gears of all types and gearboxes of all types used in machines except for land vehicles, namely, planetary gearboxes; right angle drives for machines; transfer cases not for land vehicles; two-speed and multi-speed gearboxes for land vehicles and transmissions for machines; gear heads, and gear reducers except for land vehicles; internal and external splines for two-speed mechanical drive power transmitting mechanisms in the nature of gear reduction units for machines except for land vehicles; internal and external splines for two-speed hydraulic drive power transmitting mechanisms in the nature of gear reduction units for machines except for land vehicles; internal and external splines for two-speed electrical drive power transmitting mechanisms in the nature of gear reduction units for machines except for land vehicles; internal and external splines for final drives, and planetary gear drives except for land vehicles; internal and external splines for hydraulic, electric and mechanical apparatus for gear changing for machines except for land vehicles; internal and external splines for torque converters used in machines except for land vehicles, internal and external splines used in multi-speed and two-speed gear changers to propel or position off-road machinery or components thereof and to increase, decrease or otherwise change or alter the torque or speed of the machine or components thereof; internal and external splines used in gear changers to propel or position off-road machinery or components thereof and to increase, decrease or otherwise change or alter the torque or speed of the machine or components thereof; internal and external splines used in gear changers to propel or position off-road agricultural machinery, namely, agricultural tractors, combines, harvesters, sprayers, and wind-rowers; internal and external splines used in gear changers to propel or position off-road construction machinery, namely, wheel loaders, backhoe loaders, skid-steer loaders, compact track loaders, excavators, mini-excavators, trenchers, and motor graders; internal and external splines used in gear changers to propel or position road rehabilitation machinery, namely, pavers; internal and external splines used in gear changers to propel or position lifting machinery, namely, lift trucks, access work platforms both boom and scissors, and telehandlers; internal and external splines used in gear changers to propel or position off-road mining machinery, namely, rigid haul trucks, articulated haul trucks, long-wall equipment, underground equipment; and, internal and external splines used in rear wheel drives for machines except for land vehicles