The Glock 17 is the original 9×19mm Parabellum model, with a standard magazine capacity of 17 rounds. Several modified versions of the Glock 17 have been introduced.
- The 17C was introduced in 1996 and incorporated slots cut in the barrel and slide to compensate for muzzle rise and recoil. Many other Glock pistols now come with this option, all with a “C” suffix on the slide.
- The 17L was introduced in 1988 and incorporates a longer slide and extended barrel. Initially, the Glock 17L had three holes in the top of the barrel and a corresponding slot in the slide; however, later production pistols lack the holes in the barrel. The Glock 17L is effectively discontinued and replaced by the Glock 34.
- The 17MB is a version with ambidextrous magazine catch. This model, along with the other MB variants, was discontinued upon the introduction of the fourth-generation models, which features a reversible magazine catch.