The ProMagA(R) RollerMag reinvented the wheel when it came to AR magazines by adding wheels to their friction-free, anti-tilt follower. This revolutionary Rollerfollower creates a smooth, rolling, controlled feed for maximum friction reduction. The guided, anti-tilt follower rolls smoothly without contact to the body. Fits all AR-15 pattern rifles 5.56 NATO/.223 Remington 30 rounds Polymer body Rollerfollower for friction reduction Heat-treated chrome silicon wire spring Order today!