So I just picked up a 20" FN A4 upper w/ Aero A2 lower, not a fan of the lower but paid $500 for the entire rifle. Figured I would sell the lower and get a Knights lower or Colt. Just wanted some info on the upper I bought.

So the barrel has FNMI MP 1/7 markings, the receiver has "F & keyhole markings". Just wanted to get some info on what exactly and where exactly this upper came from?

Thanks
Mike