Abstract: The invention is basically a device that injects colors into the plastic at the nozzle end of the injection screw. To place the invention on an injection screw, one drills a small opening in the injector barrel just before the injection nozzle. One then attaches a check valve to this opening. To the check valve, a color tube, a flow control valve, and a color pump are attached. Attached to the color pump are the color hopper with liquid color pigment and the high-pressure air supply line. The high-pressure air runs the color pump and pumps the color pigment under pressure into the flow control valve, the color line, the check valve and the barrel. For each color that an individual wishes to add to the plastic, one uses a separate opening, check valve, tube, flow control valve, and color hopper.