This magazine upgrade you will get additional rounds in the factory 10 and 12 round mags. These modifications are not permanent and easily install in minutes. This upgrade will increase your Smith & Wesson M&P 22 pistol magazine's capacity from the factory 10rd or 12rd magazines to 15 rounds. With one (1) in the chamber and 15 in the magazine, that's 16 rounds in the gun! This kit is NOT for the COMPACT M&P22. We do offer kits for the Compact among others.