Standard TIE fighter, modified for export to allied states and organizations authorized to purchase Imperial hardware. The TIe fighter's wings are radiators, dumping excess energy from the matter reactor. Removing the forward two radiator sections, provided improved visibility but it reduced the time the reactor could be kept at full output. In the case of Guild and Consortium operations; this wasn't a problem as almost all sane pilots didn't chance flying at full combat power inside an asteroid belt or planetary debris field. There were, however always exceptions.
As seen in Star Wars; Rebels, the chevron wing design looks good. The bold single colour was used for easy recognition in the environments they would be operating in.