Elks, Dugan
There are only a few of these nappies known, thought to have been prototypes but never produced in quantity. The one at left sold in 1995 for $7,000 and is the only one known in this shape. It sold again in 2018 for $10,000.
This ruffled versions brought $7,500 in 2014 while another had brought $6,500 in 2007.

Updated 6/26/2018