E-40 was the designation of the Galactic Empire's space production facility that made TIE/D Defenders and TIE/ad Avengers for Imperial Navy. It was in the Triton system of the Mid Rim. In 0 BBY, during the Galactic Civil War, a rogue admiral named Harkov betrayed the Empire and used the E-40 facility to make fighters for his small fleet. The facility was recaptured by Imperial Marines and spacetroopers when Grand Admiral Thrawn's Task Force Whirlwind engaged Harkov.