This is a nice vintage pre war Gibson tenor banjo. Gibson made these from 1935 into the early 40s and most of them had no serial numbers. This is a clean banjo and as best I can tell everything is original except for the strings and head which I replaced.  I don't see any markings other than the numbers the owner put on the back of the neck heel, very common at the time.    Going over it all the neck and rim are in excellent shape. It has the original pre war one piece flange and hooks which are in very good shape. The flange does pull up a little but there are no cracks, repairs or alterations. As far as I know the tailpiece is also original as are the Grover tuners. This one has very good original frets and a good set up so its a good tenor banjo as it is. Many convert these to 5 string banjos by adding a flat head tone ring and a 5 string neck. I would highly recommend Jimmy Cox at coxbanjos.com for that as he does great work at reasonable rates. The woods make some of the most important contributions to banjo tone and there is nothing quite like old growth Eastern maple that has aged 75+ years and the original Gibson flanges are desirable.     The resonator looks more beat up than the rest of the banjo but it is certainly a Gibson resonator and it is not the same as the resonator on my Kalamazoo banjo from this same era. I have 2 of these TB-00s for sale but the other one has not been listed yet . No parts have been changed or swapped on these and this one is as I received it from an estate some years back except for the new head.I will guarantee that this is an original Gibson TB-00 with the original finish, tuners and one piece flange in good playing order with very good frets still.Buyer to pay actual shipping cost, probably about $ 40 to most of the US but a bit more to the West Coast.