BCM 11.5 ELW-F (Enhanced LW Barrel Fluted) Upper Receiver Group (standard) MCMR 10. Comes with A2 FH.
Features:
M4 Feed Ramp Barrel Extension
M4 Feed Ramp Flat Top Receiver
T-Marked Upper Receivers
USGI 1/7 Twist Rates
USGI 5.56 NATO Chambers
Chrome Lined Bore and Chamber
Manganese Phosphate Barrel Finish
Mil-Spec F-Marked Forged Front Sights
ELW FLUTED Profile Barrel
HPT (High Pressure Test) Barrels
MPI (Magnetic Particle Inspected) Barrels