Over the years I have Purchased 2 M&P 15-22's. I am left handed. The first is setup like my 3 gun rifle for short range practice. The second, I purchased for my left handed grandsons to shoot, you can't ignore the cool factor. On both these guns the thumb safety was molded so that it was reversible for right or left hand operation. Two months ago I purchased a third rifle for rimfire rifle optic shooting in local steel challenge matches. The safety on the most recent rifle is not reversible. I contacted S&W, the rep said he would send me a reversible safety. The one I received was not. A second call to S&W and a different rep told me he didn't know much about the rifle but would find out and call me back. A few days later the rep did call back and told me it was a patent infringement issue and they had to stop making the reversible safety. If you are a lefty and want a left hand safety, you will now have to go to an after market part. A standard Ambi safety will not work on the 15-22 as the lower is thicker. I purchased a BAD 15-22 compatible safety that works well.