Here for sale is a genuine 1930's National Duolian and to our knowledge its all original But it appears to have a newer cone. It has many markS and finish is aging but common for these guitars from this era. Its also hard to know for certain but the tuners may have been changed and has had the benefit of a Replacement of frets without fret wear to speak of. This guitar has action suitable for slide or fingerstyle playing and comes newer hardshell case and lots of mojo. Serial Number C1716