I bought this a couple of years ago and used it to check the chamber in one un-chromed AR barrel.
What a great tool! It worked like a champ and due to its design it is virtually impossible to screw up your gun or the reamer. After using it, I oiled it up to protect it and put it away.
I would ordinarily not sell such a useful tool but I need to raise money for match fees for a few pistol competitions I want to attend. Michiguns sells this tool for $240+$10 for shipping.
I will sell mine for $200.00 shipped saving my buyer a cool $50 on a tool with no wear at all. If you want more info on the tool, see Michiguns website
Here are a few pics of it, pretty neat that you can store the bit inside the housing to protect it.