What you’re looking at here is a conversion kit plus complete upper with a Glock-compatible 9mm BCG! It has a 8″ 9mm Parabellum 1-in-10″ twist match-grade barrel, enhanced feedramps for maximum reliability across all ammo types, A2 flash hider on a 1/2×36 thread muzzle, free-float 7″ MLOK handguard, and a slick-side billet upper receiver. The TorkMag Magdapt™ 17 conversion kit is the original AR15 magazine well adapter for Glock™ 9mm/.40 S&W/.357 SIG magazines and the only Glock™ magwell adapter on the market to not add any moving parts to your AR15 lower. Fully compatible with aftermarket AR15 ambidextrous magazine releases. Stick with your muscle memory for changing mags with the Magdapt™ 17 conversion kit! Modify your Glock™ magazines to lock into AR15 mag catches with the included trim guide, or use TorkMag 20rd G17 magazines that are pre-molded with an AR15 mag catch slot. In less than a minute, you can still switch back to 5.56mm without any permanent changes to your lower. The Magdapt 17 does not hold the bolt open on empty.