Garmin GPS devices read and display mapping according to its gps mapping programs. As I know garmin gps mapping display in the following hierarchy:
* City Navigator
* City Select
* MetroGuide
* MetroGuide Canada
* BlueChart g2 & BlueChart g2 Vision
* BlueChart
* LakeMaster
* Lakes
* Fishing Hot Spots
* US Recreational Lakes with Fishing Hot Spots
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