STANAG magazine
The magazine conceived for the 5.56×45mm NATO version of the rifle is called the Magpul PMag, a high-impact, 30-round, polymer magazine claimed by Magpul to be significantly more resistant to wear, shock, and harsh environments than other counterparts on the market. The PMag is STANAG 4179-compatible, as it will readily fit any STANAG magazine firearm, including the M16 rifle family.