The Glock 19M - 9mm was developed for use by the FBI, and served as the predecessor to the Gen5 line. The 19M includes all of the standard Gen5 features, such as the straight front grip area, flared magwell, nDLC finish, as well as the Glock Marksman Barrel. Additionally, to meet the FBI's service standards, the 19M also includes Ameriglo Agent Night Sights, the Extended Ambidextrous Slide Stop Lever, and the unique rounded "FBI" magazine catch.