Abstract: A shaft-hub connection system with angular play for bidirectional transmission of driving torque, comprising a shaft, a hub provided with a hole inside which the shaft is accommodated, and elements for connection which are interposed between the hub and said shaft. The connection elements comprise at least one functional assembly which comprises a slot in which a corresponding coupling element is accommodated so that it can move and is adapted to assume alternately a first position, in which it is retracted within the slot, a second position, in which it protrudes partially with respect to it along a first orientation, and a third position, in which it protrudes partially with respect to it along a second orientation, elastic compression elements interposed between the slot and the coupling element, a first seat and a second seat for the abutment of the coupling element.