The Spike's Tactical ST-15 LE Complete Upper is a mission-ready 5.56x45mm NATO assembly built to full Mil-Spec standards for law enforcement and civilian use. It features a 16 M4 profile steel barrel with a black phosphate finish and a 1:7 twist rate. The upper is built on a 7075-T6 aluminum receiver and utilizes a carbine-length gas system with an F-marked A2 front sight base. This classic LE configuration includes M4 double heat shield handguards, a Spike's Tactical Mil-Spec M16 bolt carrier group, and a standard A2 flash hider, offering a duty-grade foundation for any AR-15 carbine.