| LMT MRP Complete Upper Receiver w/ 16 Inch Chrome Lined 1:7 Twist 5.56mm Barrel - M-5-6C7-CX-SF-X-XXX Lewis Machine and Tool MRP™ and CQB MRP™ Complete Upper Receiver Assemblies Include: Does NOT include bolt carrier Group MRP = Monolithic Rail Platform CQB = Close Quarter Combat |