The Smith & Wesson M&P Shield Plus 13 Round 9mm Luger Magazine has a black finish and holds 13 rounds of 9mm Luger ammunition.
I bought several magazines for my S&W, M&P Shield Plus that seem to have the same flaw. The magazine jams when pushing the mag release button. After examining several new mags, I discover the follower sits too high in the body of the magazine. Inside the gun, the follower will slip past the slide ejector. If you are conceal carrying, you need to be aware of magazines jamming and you may have to pull it out by hand. I switched back to my SIG to carry and M&P for dry fire practice. I found keeping the mags loaded does fix the problem and allow the magazine to work properly; however, be aware that your mags are loaded in the house if you practice dry firing. Hope this helps.