It is the part that is a sub-section of Three Point suspension system and allows hydraulic lifting levers of tractor to grip seed drill. As the load of machine is added on this shaft, it is too important to use true shaft according to the size of machine, and to replace with the new one when is it required. For the machines with 3 meters work extend in maximum, crank shaft is used in type of Category II. As for the oversize machines, crank shaft is used in type of Category III.