The 7.62x51 NATO (.308 Winchester) PMAG 25 LR/SR GEN M3 Window is a lightweight, cost effective, high reliability magazine for SR25/M110 pattern rifles featuring true 25-round capacity, constant-curve body, anti-tilt follower, snap on Impact/Dust Cover, and features transparent windows to allow rapid visual identification of approximate number of rounds remaining. The PMAG 25LR/SR brings GEN M3 improvements to the LR line along with "more of a good thing" in the form of 25 rounds of capacity. Keep track of those rounds with MagLevel™ Window functionality, for the first time, now available in a 7.62 PMAG. Commercial rifle compatibility includes the new Armalite AR-10A, Bushmaster .308 ORC, Colt LE901-16S, CORE Rifle Systems CORE30, DPMS LR308, JP Enterprises LRP-07, KAC SR25, LaRue OBR, Les Baer .308, LMT .308 MWS, LWRCI REPR, Mega Arms MATEN, POF P-308, Remington R-25, Ruger SR-762, S&W M&P10, SIG716, and others. NOTE: NOT compatible with Armalite AR-10B, Noveske N6, Springfield Armory M1A, Rock River Arms LAR8, FN SCAR 17S, PTR-91, HK417 or any other rifles that utilize M14, FN FAL, or HK 91/G3 patterned magazines.