The apparatus is removably mounted on a copying machine, for feeding a web, such as an output medium of a computer, as it is paid out of a web supply tray. The apparatus comprises pin chains for driving the web, a roller for reversing the direction of movement of the web driven by the pin chains, a conveyor pivotally movable between a horizontal position and a vertical position, an operating device for operating the pin chains, a discharged web receiving tray disposed beneath the web supply tray, and a window for taking readings on the scale attached to the copying machine and indicating the sizes of copy sheets.