Luth-AR Commerical Scallop Carbine Buffer Tube AR-10/ AR-15 5.56x45mm NATO/ 7.62x51mm NATO 7.25in Length 6 Positions 6061-T6 Aluminum Anodized Black. This Carbine Buffer Tube works with their MBA-3 MBA-4 and MBA-5. Specifications for Luth-AR AR-10/15 Commerical Scallop Carbine Buffer Tube - 6-Position: Manufacturer: Luth-AR Color: Black Finish: Type III Hard Coat Anodized Fabric/Material: 6061-T6 Aluminum Gun Make: AR Platform Gun Model: AR-10 M4 M16 AR-15 Gun Type: Carbine Length: 7.25 in Condition: New Caliber: 7.62x51mm NATO 5.56x45mm NATO .223 Remington .308 Winchester Weight: 5 oz Gas System Length: Carbine Length Package Contents: Luth-AR AR-10/15 Commerical Scallop Carbine Buffer Tube - 6-Position What firearm models does the manufacturer say Luth-AR AR-10/15 Commerical Scallop Carbine Buffer Tube - 6-Position is compatible with? The manufacturer says that Luth-AR AR-10/15 Commerical Scallop Carbine Buffer Tube - 6-Position is compatible with AR-15 M4 M16 AR-10Luth-AR BS-15SC: Commerical Scallop Carbine Buffer Tube AR-10/ AR-15 5.56x45mm NATO/ 7.62x51mm NATO 7.25in Length 6 Positions 6061-T6 Aluminum Anodized Black