I have a 9mm barrel that came on an upper I purchased. There are no markings as to the manufacturer, but I was told it was cut and threaded by Adco, although I have no way of verifying this. It is around 8" long and threaded 1/2"x36". The threads are concentric as verified by running my can with a buddy's thread adapter. It measures .85 right behind the muzzle, .650 at the narrowest point, and 1" in front of the extension. This is a great barrel, but I needed 1/2"x28" threads. So rather than have it cut and threaded or run an adapter, I just bought another barrel from Adco. I'm asking $150 shipped or I would consider a trade for a 10 1/2" or so 9mm barrel threaded 1/2"x28", a ramped 9mm bolt, a VM Hytech Uzi mag block, or a short 7.62x39 AR barrel. I can accept discreet paypal + fees or USPS money order. IM or email with any questions. Thanks.