AR15 6MM ARC 20" Upper Receiver ARC 6MM AR15 Upper

This AR-15 complete 6mm Arc upper has a 20" heavy contour barrel with a 416R stainless finish with straight flutes, and features a 1:8 twist rate, with a rifle length gas system. It includes a 15" MLOK rail, an M4 flat-top forged upper receiver, a bolt carrier group, a flash hider, and a rear charging handle. This 6mm Arc upper is compatible with any mil-spec AR-15 lower.