I Would like to trade one new, unopened set of round wound strings for a used set of med gauge flats. well worn is fine but I would prefer the end windings be in decent shape. Please specify gauge when replying. I have the following new, unopened for you to choose from; - Ernie Ball Reg. Slinky .050-.105 Long Scale - D'Addario XL Nickel wound med. .050-.105 Long Scale -Fender 5250XL Nickelplated Steel .040-.095 Shortscale Again, These are rounds... I'm looking for flats. THANKS!