Tuff-Luv Apocalypse Series leather Case Cover for Sony Walkman NWZ-S540 series (NWZ-S544 NWZ-S545) + Wrap-M
It works for the protection of the Sony Walkman.  I don't like the cord wrap and would have preferred a clip for the belt.  Overall, a good product and fits the 545 model well.  Tt is doing what I expected, protecting my MP3 player.