| LMT Monolithic Barrel Assembly 18" Stainless Steel CQB MRP 6.8 SPC - L7GA1B Lewis Machine and Tool's MRP™ barrel assemblies are unique to the Monolithic Rail Platform system. With the proper installation wrench, an operator can customize his rifle for the mission at hand without armorer or gunsmith assistance. 18" Stainless Steel 6.8 SPC CQB MRP™ barrel assembly, 1:10" twist. Designed for the CQB MRP™ and MRP™ upper receiver |