needed ] Feed system 10, 20, 32, 36 and 50 round box magazine. The Intratec TEC-DC9 (also known simply as the TEC-9 ) is a blowback -operated, semi-automatic 9x19mm Parabellum caliber firearm , classified by the U.S. Bureau of Alcohol, Tobacco, and Firearms as a handgun . Designed by Intratec ,