Several companies have developed 9mm conversion systems designed for use in standard AR-15 lowers and uppers. However, feeding a 9mm magazine through a standard AR-15 magazine well presents some issues. Typically, this has been solved by the use of magwell inserts, but Mean Arms tackled the issue with a different take: why not change the magazine itself? The Mean Arms AR-9 Endomag Conversion Kit takes any standard Gen 2 or Gen 3 Magpul PMAG and allows it to be converted to feed 9mm rounds. The conversion is built for use with Glock®or Colt 9mm bolt-carrier groups. The kit comes ready to convert 10-round magazines, but it can be modified to fit 20- or 30-round magazines. No magwell adapter is needed for use with the Mean Arms AR-9 Endomag Conversion Kit, and the company ensures reliable performance with all brands of 9mm ammo.