SD Card

 

When I down load files to an SD card can I use that card in other GPS units or am I limited to only Garmin or only that specific Garmin model?

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If they're POI files, you can use them in any GPS that accepts the file format i.e. *.gpx, *.csv etc.

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nüvi 3790T | Those who make peaceful revolution impossible, will make violent revolution inevitable ~ JFK

Sd Card

An SD Card is simply a storage location that stores what ever is copied to it. The program that reads the file must be able to read the file format indicated by the extension(letters after the period) For example an mp3 player will read an .mp3 extension. Windows media player a .wma extension. Therefore the extension of the file copied from Garmin can be read by a compatible program.

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Zuma314