The document provides specifications and part numbers for J-20 wrap spring clutches with a DCB-4 metric bore. Key specifications include a maximum speed of 1200 RPM, static torque of 120 in-lb, and maximum anti-overrun and anti-back torques of 25 in-lb and 80 in-lb respectively. The document also lists replacement parts for the DCB-4 clutches by item number, part number, description, and rotation/voltage.