Abstract: A braking system for a freight module, crane module, or the like which is suspended for movement on an overhead guiding rail having the form of an I beam with upper and lower horizontal flanges and a vertical web in which braking results from the pincer action of pivoted pincers having upper arm portions pressing brake shoes, one mounted on each pincer, against the vertical web of the I beam. The lower arm portions of each pincer diverge outwardly and downwardly to provide a triangular opening below the pivot pin and a rectangular opening at the bottom ends. A tension spring is mounted at the base of the triangular portion. A parallelogram shaped cam disc having curved ends is mounted for opening movement between base plates at the sides of the rectangular opening. A motor and shaft rotate the cam through a predetermined arc to apply the braking movement in a controlled manner to gradually slow down the module and avoid oscillations of the module.