The next-generation PMAG 30 GEN M3 Window is a 30-round 5.56x45 NATO (.223 Remington) polymer magazine for AR15/M4 compatible firearms that features transparent windows to allow rapid visual identification of approximate number of rounds remaining. Along with expanded feature set and compatibility, the GEN M3 Window incorporates new material technology and manufacturing processes for enhanced strength, durability, and reliability to exceed rigorous military performance specifications. While the GEN M3 is optimized for Colt-spec AR15/M4 platforms, modified internal and external geometry also permits operation with a range of additional firearms such as the HK 416/MR556A1/M27 IAR, British SA-80, FN SCAR MK 16/16S, and others. Similar to the MOE PMAG, the GEN M3 Window features a long-life USGl-spec stainless steel spring, four-way anti-tilt follower and constant-curve internal geometry for reliable feeding, and simple tool-less disassembly to ease cleaning. In addition, a redesigned bolt catch notch in the rear of the magazine provides increased bolt catch clearance, while an over-travel stop on the spine helps ensure the magazine will not over-insert on compatible platforms. Low profile ribs and new aggressive front and rear texture gives positive control of the GEN M3 in all environments, and a paint pen dot matrix has been added to the bottom panel of the body to allow easy marking by the end user for identification.