 The passive exoskeletal vest was designed to reduce muscle fatigue for manufacturing workers. It provides assistance with the shoulder joint while allowing for full freedom of movement. The device has two modes, one for static tasks and another for precision and dynamic tasks. In the static mode, the arm can be locked into any desired height, while in the other two modes, the arm moves freely without any resistance. The device was tested on seven subjects performing static, precision, and dynamic tasks. The results showed that the exoskeleton reduced muscle fatigue, did not restrict the range of motion, and provided a comfortable fit. This article was authored by Zihayu Du, Zifeng Yan, Tian Tian Huang, and others.