If your chartplotter came with built-in BlueChart® g3 coastal charts or LakeVü™ g3 inland maps, a plug-in microSD™ card makes it easy to upgrade with our latest Garmin Navionics+ all-in-one mapping solution. Check chartplotter compatibility. Includes a 1-year subscription. For Garmin Chartplotters Only. Some features require subscription. See Navionics website for compatibility, coverage details & full list of features.