Aim Sports W15TU Warrior Systems 50Rd 5.56X45mm Nato Drum For AR-15 Gray Cerakote Aim Sports Drum Magazine For Your AR-15. Caliber: 5.56X45mm Nato Capacity: 50Rd Model: Warrior Systems Capacity: 50 Manufacturer: Aim Sports Mfg Number: W15TU Model: Warrior Systems