If you live in a state that does not allow threaded barrels, we can remove the barrel threads before shipping out one of our uppers or barrels. Each thread is machined down and touched up with cold blue for color and finish. Please use this part number to add to any M-11, Mac-10, or Master Piece Arms upper or other pistol or rifle barrel. Send us the barrel only, we charge $12.99 for return shipping and insurance. Call or email with any questions.