PANZER ARMS M4 Tactical 12 Gauge 3" 18.5" 5 Round Semi-Auto Shotgun w/ Fixed Standard Stock | Black The Panzer Arms M4 Tactical, an exceptional shotgun that pays homage to the legendary M4. This reliable and durable semi-automatic 12 Gauge shotgun utilizes an inertia-driven system, ensuring smooth performance during shooting. With its familiar handling, comfortable ergonomic furniture, extended tube magazine, and the renowned M4 gas system, this firearm is designed to provide optimal shooting experiences. One of the outstanding features of the Panzer Arms M4 Tactical is its compatibility with parts from the Benelli M4. This means you have the flexibility to customize and enhance your shotgun with ease, knowing that the parts are 100% interchangeable with the Benelli M4.