Your Garmin help, please

Hmm. Manufacturer 256 doesn't appear in the example fit source files (although I doubt I've got the latest version). Could be reserved since it's 2^8.

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define FIT_MANUFACTURER_INSIDE_RIDE_TECHNOLOGIES                                ((FIT_MANUFACTURER)93)
define FIT_MANUFACTURER_SOUND_OF_MOTION                                         ((FIT_MANUFACTURER)94)
define FIT_MANUFACTURER_STRYD                                                   ((FIT_MANUFACTURER)95)
define FIT_MANUFACTURER_DEVELOPMENT                                             ((FIT_MANUFACTURER)255)
define FIT_MANUFACTURER_HEALTHANDLIFE                                           ((FIT_MANUFACTURER)257)
define FIT_MANUFACTURER_LEZYNE                                                  ((FIT_MANUFACTURER)258)
define FIT_MANUFACTURER_SCRIBE_LABS                                             ((FIT_MANUFACTURER)259)
define FIT_MANUFACTURER_ZWIFT                                                   ((FIT_MANUFACTURER)260)
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