The TRD-2 sparring droid, a training droid created by Balmorran Arms, shared design elements with their SD-series battle droid. These droids were intended for use in the instruction of Imperial officer cadets. However, instructors believed that the TRD-series, due to a reduction in training deaths, did not possess the necessary aggressive tendencies found in dedicated combat droids, leading to their removal from training programs. Subsequently, the Galactic Empire repurposed the TRD-series for tasks like crowd control and corporate security, while certain other groups continued to employ them for their initially intended training functions.