AA-12,

AA-12, originally designed and known as the Atchisson Assault Shotgun, is an automatic combat shotgun developed in 1972 by Maxwell Atchisson. The most prominent feature is reduced recoil. The current 2005 version has been developed over 18 years since the patent was sold to Military Police Systems, Inc. Wikipedia
Manufacturer: Maxwell Atchisson
Designed: Original design: 1972; MPS design: 2005
Rate of fire: 300 rounds/min
Feed system: 8 rounds in box magazine, 20 or 32 rounds in drum magazines
Action: API blowback
Cartridge: 12 Gauge
Sights: Iron sight, 2× zoom optical scope