Regarding compatibility, the Garmin Fenix 5X, 6X, and 7X series are interchangeable. For example, if you choose the Fenix 5X model, it will be compatible with the Fenix 5X Plus, 6X, 6X Pro, and 7X. That is to say, the Fenix 5, 6, and 7 series are mutually compatible.
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