i have a 64gb on my garmin xt the extreme pro i have on my laptop in use
in any case the card has to be formatted FAT other formats like exfat,ntfs etc are not recognised by the system
the card must be plugged in while the device is running otherwise it will not work either
then have fun with it
greetings francis

As I don't have a Garmin, unfortunately I can't answer that. However, if it meets the specifications of the sat nav in terms of size, I assume it does.
Best regards
Dirk

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