This 30-round magazine from ProMag is perfect for AR-15 owners looking for an extra mag. Made of black polymer this magazine also features a patented guided roller follower that ensures anti-tilt performance with improved friction reduction.In addition the spring is formed from heat-treated chrome silicon wire for added durability.ProMag AR-15 223/5.56 Magazine w/ Roller Follower30 Round CapacityFeatures an Anti-Tilt Roller Follower Order your 30-round AR-15 magazine online today!Searching for AR15 ammunition? Shop our online selection of cheap 5.56/.223 Rem ammo from the top brands you trust