Right, I found that description as well.An A.O.W. is a weapon classification utilized by the B.A.T.F. to categorize and restrict those weapons that are not considered to be a rifle, pistol, or machinegun. An example of an A.O.W. is a short-barreled shotgun or a pen-gun. They are class III (NFA) items, and must be approved for transfer to individuals at the federal level (with a "form-4"). Cost to transfer= $5.00
S.B.S. - Short Barrel Shotgun
Short barrel shotguns will have a barrel less than 18", and will have a full stock. These guns require a $200.00 transfer tax.
This is a A.O.W.