Meeting the overall length requirements for a 14MM competition magazine, the PMAG 21 GL9 offers additional capacity without the need for expensive extensions. The PMAG 21 GL9 is compatible with all full-size, compact, and sub-compact double-stack Glock 9mm variants with some protrusion below the grip. It features a flared, easily removeable floor plate, magazine indicator window on both sides of body at 1,15, and 21 round remaining, and drops free loaded and unloaded. Specifications and Features: Caliber: 9mm Luger Capacity: 21 Finish: Black Model: PMAG Material: Polymer Model Fit: All Glock 9mm Capacity: 21