I use a Wahoo Kickr and My PC with an ANT stick to Ride with Zwift. When I search for Devices I see two to choose from, even though I have just one KIckr. So I am curious to know which to choose. One of the options is the Number of the Kickr. The other option has an FE-C before the number. There is a difference between them. When I choose the FE_C and the number choice the spindown wrench is an option. If I don’t choose the FE-C number option the spindown calibration wrench disappears. I would like to know more about the differences between these two choices.