This A-3 Flat top is the military standard M-4 Flat Top receiver with the M-4 Feed Ramp cut into the receiver. This upper receiver is only for barrels and barrel extensions with the M-4 feed ramps.
This A-3 Flat top is the military standard M-4 Flat Top receiver with the M-4 Feed Ramp cut into the receiver. This upper receiver is only for barrels and barrel extensions with the M-4 feed ramps.