The Sig M400 is a true AR platform tactical rifle designed for use in law-enforcement, military operations, or the sporting field. The M400 provides unparalleled accuracy, with a 16" chrome-lined and phosphate coated barrel that provides maximum durability and corrosion resistance. The rifle runs on a direct impingement gas-operating system with rotating locking bolt. Every M400 comes with an A2 Type flash suppressor. A 7075-T6 aircraft grade aluminum forged lower receiver adds to the durability and reliability. The SWAT model features a two-piece aluminum quad-rail, a six-position collapsible stock, and an F-marked post front sight with a flip-up adjustable rear sight. This model features a bullet button for California compliance.