Manufactured in 1965, early non-chrome lined barrel with 1-12" twist. Post front and windage adjustable flip up two leaf rear peep sights, early style three-prong flash hider, gas block with bayonet lug, ventilated triangular handguard, correct early style upper with fixed carry handle, no forward assist or deflector, correct early style bolt carrier without serrations, large pin hole, and chrome bolt.