The NRC Robotic Exoskeleton (NREX), an upper-extremity, rehabilitation robotic exoskeleton developed for daily life exercises, and treatment of hemiplegic or spinal-cord injured people, was improved by the National Rehabilitation Center, Korea. The shoulder module, which had restricted movement, was improved via additional passive-axis movements with rubber bands. In addition, NREX can now be used for either left- or right-arms by changing only two parts of the robot arm. We focus on the improvement of NREX mechanism to reduce cost and improve usability.