RRA/Bushmaster A1 Superlight Carbine.
Lower is RRA forged with A1 buttstock, and upper receiver is Bushmaster A1 with 16" Superlight barrel. Rifle is in perfect condition, never fired, except upper was test-fired at factory. I bought the lower from a local gunshop, put the A1 buttstock (still have the A2) on it and bought the upper direct from Bushmaster. I am selling this complete rifle for $690. Rifle sold with no accessories, ship to FFL.
Have pics for those interested.