The gearbox is the main mechanical component in the kinematic chain of agricultural machines. It is normally driven by the tractor power take-off via the PTO shaft and transmits motive power to the various other components of the machine. Torque can also be transmitted to the gearbox by hydraulic engines or belt pulleys, as well as by chain gears. Gearboxes always have an input shaft and at least one output shaft. If these shafts are positioned at right-angles to each other, the gearbox is an ORTHOGONAL SHAFTS gearboxes (series L – series T – series V – series E – series S – series G – series MF – series O – reducers fo cutter bars – square baller), more commonly called a right-angle drive.

If the shafts are parallel to each other, the gearbox is known as a PARALLEL SHAFTS gearboxes (series P – series PE – series PA – series I).

Based on the gears and their number of teeth, the CMR Group range of gearboxes includes: