Changing data fields and dashboard on a Garmin eTrex 20 and 30- Log into online resource) > Courses > Garmin - Units > eTrex 20x and 30x > Changing data fields and dashboard on a Garmin eTrex 20 and 30 - Video on Online Course
You can also when logged in view videos for the newer etrex22x & 32x units which you will still find useful for the older model as very similar and there are a lot more training videos for the newer version.
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