Lancer Systems L5 Advanced Warfighter AR Rifle .223 Remington 5.56x45mm NATO 30 Round Rifle Magazine LCR. 300 Blackout ammunition (200+ grain) the Lancer L5AWM 300BLK magazine features an updated internal geometry which allows longer heavier cartridges to stack properly increasing feeding reliability when compared to a traditional .223/5.56 magazine. The outside of the mag body is molded with distinctive .300 Blackout markings and the magazine ships with a contrasting flat dark earth floor plate for easy visual identification. Specifications for Lancer Systems L5AWM AR-15 .300 Blackout 30 Round Rifle Magazine: Manufacturer: Lancer Systems Color: Opaque Black Magazine Capacity: 30 Round Caliber: 5.56x45mm NATO .223 Remington Gun Make: AR Platform Gun Model: AR-15 Gun Type: Rifle Quantity: 1 Included Accessories: Standard Condition: New Country of Origin: USA Package Content: Lancer Systems L5AWM AR-15 .300 Blackout 30 Round Rifle Magazine What firearm models does the manufacturer say Lancer Systems L5AWM AR-15 .300 Blackout 30 Round Rifle Magazine is compatible with? The manufacturer suggests that Lancer Systems L5AWM AR-15 .300 Blackout 30 Round Rifle Magazine is compatible with AR-15Lancer Systems L5 Advanced Warfighter AR Rifle .223 Remington 5.56x45mm NATO 30 Round Rifle Magazine LCR999000428004