This Model Defender M18 Ammo Pouch is constructed with MIL-SPEC 500 denier Nylon, and is capable of holding 17 or 21 round magazines. Featuring an open top with integrated bungee retention and quick release retention tabs, an OCP pattern and a low profile design, this pouch is also stackable with the M4 Ammo Pouch as needed. Made in the USA!