BlueChart g3 Vision HD – VUS517L – Alaska South – microSD /SD Coverage:Alaska, from Prince of Wales Island to Point Lay on the North Slope, including Glacier Bay, the Kenai Peninsula, and the Aleutian Chain in full. Bathymetric coverage of the Gulf of Alaska, Bristol Bay and United States waters in the Chukchi and Bering Seas, and along the entire Aleutian chain including the Surveyor Seachannel, Aleutian Trench, Umnak Plateau, Chirikof Basin, and Hope Seavalley.Premier Coastal Navigation ChartsProvides industry-leading coverage, clarity and detail with updated coastal charts that feature integrated Garmin and Navionics dataAuto Guidance technology uses your desired depth and overhead clearance to calculate routes and show a suggested path to followHigh-resolution relief shading combines color and shadow to give you an easy-to-interpret, clearer view of bottom structure than contour lines aloneDepth Range Shading provides up to 10 depth ranges, enabling you to view your target depth at a glanceUp to 1′ contours provide a more accurate depiction of the bottom structure for improved fishing charts and navigation in swamps, canals and marinasExperience unparalleled coverage and brilliant detail on the water. BlueChart g3 Vision coastal charts provide industry-leading coverage, clarity and detail with integrated Garmin and Navionics data, Auto Guidance technology and high-resolution relief shading. Auto Guidance TechnologyThe Auto Guidance feature uses your desired depth and overhead clearance to calculate a route and a suggested path to follow.High-resolution Relief Shading FeatureHigh-resolution relief shading combines color and shadow to give you an easy-to-interpret, clearer view of bottom structure than contour lines alone.Up to 1′ ContoursThe closer the contour lines, the more accurate the depiction of the bottom structure for improved fishing charts and navigation in swamps, canals and marinas.NOAA Raster CartographyIf you prefer your display to have the look of paper charts, NOAA raster cartography2 is available as a free downloadable feature via the ActiveCaptain app.Depth Range ShadingThis feature p