FN 15 Upper Receiver Assemblies are meticulously built in FN's Columbia South Carolina manufacturing facility alongside US Military contract M4 rifles. Each upper receiver is supplied with and M16-style Bolt Carrier Assembly with properly staked gas key and Carpenter 158 Magnetic Particle Inspected (MPI) bolt, charging handle and FN's venerable cold hammer-forged barrel. FeaturesLightweight aluminum free float handguardCharging Handle: Mil-SpecPicatinny Rail top of receiver5 QD Points on handguardM-LOK slot on handguard: 3,6,9 o'clock surfaces