If you are a dog handler with your own WeHunt, Tracker or Ultracom GPS, you should select GPS Max.
Depending on how many devices you want to use at the same time, select either GPS Max 1, 2, 3 or 6.
For example, if you want to hunt with 2 devices simultaneously, select GPS Max 2.
If you want to hunt with 4 devices simultaneously, select GPS MAX 6.