An apparatus for advancing a plurality of components comprising a vibrating feed tray, having a plurality of interchangeable modular troughs, each sized to receive a component of a particular size. The troughs are removably and slidably secured to the tray, and can be used in any combination. One end of each trough is characterized by only one side wall. A second, parallel side wall is provided each trough by means of sharing the side wall of the adjoining trough. In the event that there is no directly adjacent trough, a side stop is positioned adjacent the open side of the trough.