A distributor plate (10) is shown for use in an impelling rotor of a vertical shaft impactor (14). Typically the impelling rotor is a chamber (12) arranged to rotate about a vertical axis A-A. Feed materials for breakage are gravity-fed into the rotating chamber (12). These materials strike the rotating distributor plate (10) which is located at the base of the rotor chamber (12). The plate has a substantially planar single-piece upper surface (24) onto which the feed materials are received. This substantially flat surface (24) facilitates rapid and easy expulsion of feed materials there across and out of the rotor chamber (12). The plate shown is a circular disc made of metal carbide. Use of a single-piece upper surface of the distributor plate (10) also will not result in the development of preferential wear sites at corners, edges, join lines etc, as can happen with the known distributor plates.