National Can I put a folding adapter on an AR Pistol?

[wired]

So, if one were to remove the KAK blades from a certain someone's AR pistols, that certain someone can do just about anything s/he wants to with them and they're still would not be an SBR or any NFA item?

Yes. Rifles have buttstocks. Short barreled rifles have buttstocks. It's one of their identifying features. Rifled barrel and buttstock.. No buttstock be it brace or traditional stock, no SBR. Just a pistol if its under 26" OAL. Over 26" OAL its a Firerarm. All this is really doing is going back to the pre SIG brace ruling days. If it looks like a buttstock or does the same thing as a buttstock, its a buttstock. No buttstock? Not a rifle or a short barrel rifle.