Scott, this should be compatible with any AR as long as it has a standard buffer tube. Carbine vs. rifle length ARs are generally only referring to the barrel and gas system length.

Scott you will need to know commercial tube or mil spec tube on your Weapon. This does not say if it is either or or will fit both. Plus just as long as it is a carbine a pistol with a brace ok.

Scott, this is compatible any AR-15 with an A2 fixed stock/tube ***Only***. The A2 is the Fixed "Stock/Tube" pictured here : google.com/search?q=ar+a2+stock&source=lnms&tbm=isch&sa=X&ved=0ahUKEwjK4NOBk6_gAhXpY98KHZ1WDtIQ_AUIDygC&biw=1280&bih=618#imgrc=Lku2w86Thv7R5M: