U-Shaped Dissipative Devices (USDDs) consist of U-Shaped Flexural Plates (USFPs) dissipating seismic energy through hysteretic behavior of steel. Recently, they are largely applied in seismic design since they have the advantage of being easy to assemble, install, and replace after a seismic event. Therefore, an essential challenge in structural engineering is to accurately predict their behavior during earthquakes, understanding the parameters influencing their energy dissipation capacity. In this study, starting from a previously refined numerical model validated with experimental tests, numerical analyses of USDD are performed to investigate the interaction among the device elements. Results reveal that the performance of USDDs is significantly affected by the interaction between their elements and the stiffness of the connection plates. This allows for design optimization, considering the expected seismic displacement, reducing the amount of steel required.