USAS-12

The USAS-12 (Universal Sports Automatic Shotgun 12-gauge) is a fully automatic gas operated shotgun made by the South Korean-based company Daewoo.
The USAS-12 is a gas-operated, select-fire weapon which is designed to provide sustained firepower in close quarter combat scenarios. It accepts detachable 10-round box magazines or 20-round drum magazines. Both types of magazine are made of polymer, and drum magazines have their rear side made from translucent polymer to tell of the number of shot shells left. It has an effective range of 40 m.