This upper assembly is for the UM15TAC18, a sturdy all around rifle platform with multiple applications. This assembly includes a dual purpose muzzle device, that reduces recoil and signature. The 15 inch handguard features a full length picatinny rail with plenty of space for mounting scopes, sights, and optics, in addition to the Key-Mod inserts for installing lights, lasers and sling attachments. The gas block is also fully adjustable, allowing the user to tune the rifle to their ammunition preference. Armalite M15 Tactical Upper Assy 18" bbl UM15TAC18