The Rock River Arms R3 Competition Upper features a Rock River Arms 18 inch stainless steel, fluted, cryogenically treated barrel chambered in .223 Wylde, with a 1:8 twist, mid-length gas system, and a 1/2-28 threaded muzzle.  Built on an RRA forged A4 flat top receiver with a low profile gas block, RRA lightweight M-LOK compatible 17 inch free float handguard, and an RRA tuned and ported muzzle brake.