These magazine modifications are for the Smith & Wesson M&P 22LR pistols. With the magazine upgrade on the full sized version, you can get 15 rounds in the magazine. With the Compact M&P version you get 13 rounds over the factory 10. This modification is not permanent and easily instals by removing the factory follower, spring and spring retainer. Insert the Shockbottle follower, new spring and the included spring retainer and slide on the factory basebad.
Please note that with the shockbottle follower, you will loose the slide lock to open on the last shot fired (the slide will not lock back on an empty mag upon firing the last shot).
Due to US restrictions I can only ship to US addresses. Sorry for the inconvenience.