Don't have the S/N, but will get it on next visit. Barrels are probably stub twist rather than good Damascus. No engraving on the lock plates, so probably the lowest field grade gun for the time. But, the case colors are wonderful, including on the hammer ears. I'll measure 20ga chambers and chokes and will try to measure the old 12ga chambers to see if they were machined to accept the chamber sleeves. When I have a little time, I'll pull out Brophy and Houchins and see if I can get a specific ID on this gun.