Shop › RRA CMPLT CAR A4 UPR 350LGD 16" 10RD RRA CMPLT CAR A4 UPR 350LGD 16" 10RD $740.00 Rock River Arms Tactical Carbine, Complete Upper Receiver, 350 Legend, 16" Barrel, RRA Operator Muzzle Brake, RRA 13" Free Float M-LOK Handguard, Anodized Finish, Black, Fits AR-15, 10 Rounds, 1 Magazine, Includes Bolt Carrier Group and Charging Handle Assembly 350L0328 Add To Cart Added! Rock River Arms Tactical Carbine, Complete Upper Receiver, 350 Legend, 16" Barrel, RRA Operator Muzzle Brake, RRA 13" Free Float M-LOK Handguard, Anodized Finish, Black, Fits AR-15, 10 Rounds, 1 Magazine, Includes Bolt Carrier Group and Charging Handle Assembly 350L0328