DURAMAG set out to re-design and perfect the Colt pattern 9mm magazines for the AR-15. With the DURAMAG SS you can feel confident that it will feed the widest variety of 9A-19 ammunition even defensive hollow points and heavy sub-sonic loads. 9mm AR-15 magazine have always been notoriously stubborn to load but loading the last round is just as easy as loading the first round with a DURAMAG SS. Other magazines fail when filling to capacity: DURAMAG will outlast and outperform all others first round to last.