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. The MRD series features an optic cut on the slide designed to be used with FN's adapter plates and is paired with suppressor-height iron sights for proper sight co-witness. This model features an all-black color pattern. One 12-round flush-fit magazine and one 15-round extended magazine is included.