Its the card he sells that comes with Rayburn/Toledo/Fork. Was trying to do Rayburn first.
The question they are asking is "Humminbird or Lowrance?". The GPX is a Lowrance format, I think. The May would be the version of the card you need.
Correction, USR is Lowrance, you may need to convert if the card doesn't have the folder with the gpx version of the files.