The 20-round TorkMag is the same size as a OEM 17-round magazine with +2 extension. The included baseplate allows for quick retrieval from a pouch under stress. Made entirely of metal replacement polymer. The G17 TorkMag has ambidextrous mag catches to ensure accessibility for southpaws using 4th Gen. Glock(TM) pistols. An AR15 mag catch is also molded into the left side of the main tube to allow out-of-the-box use with the Magdapt 17(TM) conversion kit for pistol-caliber AR carbines. Two witness holes indicate when the mag is loaded with 10 and 20 rounds. Made in the U.S.A. Mfg: Torkmag