Similar to the MOE PMAG, the GEN M3 features a long-life stainless steel spring, four-way anti-tilt follower and constant-curve internal geometry for reliable feeding. It also features simple tool-less dissassembly for easy cleaning. With low profile ribs and new aggressive front and rear texture gives positive control of the GEN M3 in all environments. It is not compatiable with the Gen M2 Ranger Floor Plates. Magpul appeared out of nowhere a few years back and quickly became the industry standard bearer in AR-15 mags and related accessories. Now their products are considered among the best in the industry. You can buy more expensive mags, but you can\'t buy them any better.