The CMMG Banshee is an ultra-compact 5.7x28mm complete upper designed for the AR-Platform. It features a 5 barrel with a 1:9 twist rate, providing a flat-shooting, low-recoil personal defense solution. Finished in Armor Black Cerakote, the upper and M-LOK free-float handguard offer a rugged, corrosion-resistant profile. This AR Style assembly is engineered for seamless operation with CMMG Mk57 lowers or standard AR-15 lowers when paired with 5.7 AR Conversion Magazines, making it an ideal choice for high-performance close-range applications. Note: When using a standard AR-15 lower receiver, this upper requires the use of CMMG 5.7 AR Conversion Magazines to ensure reliable feeding and cycling of the 5.7x28mm cartridge.