| LMT MRP Complete Upper Receiver w/ 20 Inch Stainless Steel 1:12 Twist .204 Barrel - M-2-7S2-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 |