US Patent 7980599 Identification system for pneumatic couplers

A coupler and plug system for air line uses which identifies properly mating components by the colors of the components. The coupler of the system includes a sleeve which is made in a chosen color. The plug of the system is made in the same color as the sleeve of the coupler. The plug and coupler sleeve may be anodized aluminum dyed in the same color. By choosing a plug which is of a matching color to the sleeve of a coupler, the user will choose a plug which properly mates with the coupler.