Excellent example of a very early steel bodied Style O. (serial number S400) Many of the first few hundred Style O's were made of steel instead of brass. Once they learned steel did not take nickel plating easily, they switched to brass. After the first 500 or so of the style O's were made, most all were brass after that. In that first few hundred were a bunch made of steel, as this early one was. The maple neck shows some flame and is in stellar shape, very straight with very little play wear. Original cone, tuners, tailpiece, and frets all in great shape. Original case is in beautiful shape, even has the original key to it! A great playing and sounding National with the trash can tone of the steel bodied Duolian. Very rare and hard to find, a real winner for the collector and player!