FN 66-100375:This product was meticulously crafted for the US Military\'s Modular Handgun System Competition, standing as a testament to intense scrutiny and an extensive testing phase of over 1 million rounds. Surviving the most rigorous conditions, the FN 509 stands as the apex in combat pistol engineering.Built on the durable architecture of the FNS(TM) Compact, every internal and external fragment was analyzed and refined, enhancing its ergonomic design, ammunition compatibility, and most importantly, reliability.