The Black Rain Ordnance 30 round magazine is a sturdy reliable 5.56A-45 NATO (.223 Remington) AR15/M4/M16 magazine made of advance polymer material. It is a light durable and excellent alternative to the standard M4/M16 USGI aluminum magazine.Features:Sturdy Impact resistance polymer with textured gripAnti-tilt super followerHeavy duty non-memory and non-corrosive stainless steel springMade in the U.S.A. - Produced by Amend2 Magazines