Agency Arms Mid Line Barrel, 9MM, Black Nitride Finish, Threaded And Fluted, Fits Glock 19 MLG19T/FDLC Agency Arms(R) Mid Line Barrels are for those who desire functionality as well as a unique appearance. While each of their lines maintain the same core accuracy and reliability, Agency's Mid Line focuses on additional machining enhancements and appearance while only a having modest price increase over the Standard Line models.