Fr. 2085-C - 1999 $20 FRN Solid 4s
It doesn't take a math wizard to understand that solid serial numbers are only printed for every 11 millionth or so note issued by the government. Unlike low serial numbers which are usually snapped up by tellers and other cash handlers, you have to have a sharp eye and be in the right place at the right time to catch a solid fancy serial number like this example with all 4s.
Date Sold: July 11th, 2015
Realized Price: $1053