The FN Five-seven is a semi-auto pistol in a 5.7mm caliber, after which it got its name. The Five-seven operates by a delayed blowback system. It has a concealed hammer and a single-action trigger. The pistol uses the renowned FN's 5.7x28mm cartridge. The FN Five-seven is a full-size pistol with a 4.8-inch barrel and an overall length of 8.2 inches. It features a lightweight polymer-based frame, 3-dot sights (fixed or adjustable), a Picatinny rail for mounting accessories, a smooth trigger with a predictable break for enhanced accuracy, and ambidextrous manual safety. It comes with two magazines with a standard capacity of 20 rounds, reduced capacity (10 Rd), or extended capacity (30 Rd). It also has a magazine disconnect safety system, which prevents a pistol from firing if a magazine is detached.