The RT300-155 offers a solution for managing USB cables. The cable assembly was designed to provide optimum performance. The RT300-155 has 4.0 ft of retractable cable and 4 ft of fixed length cable. The cable and the retractor have been tested to over 10,000 extensions/retractions. The AC200-125 and AC221-125 mounting hardware securely mounts the cable retractors to CNK200 and CNK221 table top units.