Duramag Speed AR-15 Rifle Magazine .223 Rem/.300 Blackout/5.56x45mm NATO 30 Round Gray w/ Orange Follower Detachable 1 Pack Aluminum. This battle-proven magazine is lightweight durable and have been the magazine of choice for OEM Law Enforcement and Military units throughout the world. The body is constructed of 6061-T6 aluminum and are type-III hard-coat anodized. It is safe for extended storage while loaded and will not flex or swell like polymer. Specifications for Duramag Speed AR-15 .223 Rem 30 Round Rifle Magazine: Manufacturer: Duramag Fabric/Material: Aluminum Magazine Capacity: 30 Round Caliber: .223 Remington Gun Make: AR Platform Gun Model: AR-15 Quantity: 1 Condition: New Package Contents: Duramag Speed AR-15 .223 Rem 30 Round Rifle Magazine What firearm models does the manufacturer say Duramag Speed AR-15 .223 Rem 30 Round Rifle Magazine is compatible with? The manufacturer says that Duramag Speed AR-15 .223 Rem 30 Round Rifle Magazine is compatible with AR-15Duramag 3023002178CPD-30RD: Speed AR-15 Rifle Magazine .223 Rem/.300 Blackout/5.56x45mm NATO 30 Round Gray w/ Orange Follower Detachable 1 Pack Aluminum