Built as a successor to FN's proven FNS series of striker-fired pistols, the 509 is FN's premier modern striker-fired duty and defensive pistol. The 509 features 3-dot style luminescent sights along with a polymer frame for reduced weight and improved corrosion resistance. The pistol also features ambidextrous controls and interchangeable backstraps to accommodate a wide variety of users. The Compact variant is designed with personal protection in mind, featuring a shorter grip and barrel length for easier concealment.