Beta Company C-Mag twin-drum 100-round magazine for 5.56x45mm AR-15 & M4 pattern platforms. BetaCo's 100 round drums are the ultimate high-capacity magazines. These magazines are made from tough polymer with steel and aluminum internals. BetaCo's magazines can be loaded and stored indefinitely, and still deliver 1,500 rounds per minute! Each magazine comes with a black carrying pouch, graphite lube, manual, and loading tool.