Rock River Arms A4 Coyote Carbine upper comes chambered in .300 AAC / Blackout with a 16″ chrome moly 1/8twist barrel. Additionally this upper includes a RRA 12.5″ M-Lok compatible lightweight free float rail and a Smith Vortex flash hider (5/8-24 thread). This is a complete upper with bolt carrier group and charging handle assembly..
