SRM Arms Inc M1216 12 Gauge 16+1 Click Image for Price Check.The 20' barrel with 3 choke tubes (cyl, mod, full) makes it a perfect turkey gun as well. This model also features a Hi-vis front sight post and an adjustable rear ghost ring sight. The CDA-12 Force is ideal for home defense. With capacity ranging from 10 rounds to 12, look no further than CSS for any of your magazine needs! This mag extension is very easy to install and works exactly as claimed. Citadel pat 12 mag extension This pump-action shotgun features a tactical pistol grip with ideally-placed finger grooves, offering improved maneuverability and quick pointing.