An epicyclic gearbox with an integral arrangement of meshing gear elements, including an annulus gear, planet gears, and sun gears, to transfer power from a motive power source to a driven element with a range of applications is provided. The annulus gear, in contact with the power source, forms an exterior gearbox input and is in meshing contact with a number of stepped planet gears supported on floating planet carriers. Each stepped planet gear is positioned internally of the annulus gear and includes two planet stages in meshing contact with corresponding sun gear stages. One of the sun gear stages is an interior gearbox output and transfers power to a machine or device to be driven. Meshing surfaces of the gear elements support helical teeth or spur teeth, with numbers of teeth on meshing gear elements selected for optimal torque transfer from the exterior input to the interior output.
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