ProMag RM40 Rollermag 40rd 5.56x45mm NATO AR-15 Polymer Detachable Magazine

The ProMag RM40 Rollermag in its Standard configuration is a 40-round 5.56x45mm NATO detachable magazine purpose-built for the AR-15 platform. Part of ProMag's Rollermag series, it delivers reliable high-capacity performance for range sessions, training, and recreational shooting.

The magazine body is molded from DuPont Zytel polymer for a lightweight, durable construction that resists cracking and warping under hard use. Inside, ProMag's patented anti-tilt roller follower feeds each round smoothly and reliably, reducing the binding and tilt issues common to standard followers in high-capacity AR magazines. The body is finished in matte Black.

Designed as a direct replacement or spare magazine, the RM40 drops into any standard AR-15 lower and accepts 5.56x45mm NATO ammunition. Whether you are topping off a stash of standard 30-rounders or running a 40-round stick for extended range time, this is a cost-effective polymer option from one of the most established names in aftermarket firearm accessories.