The Garmin LakeVu HD Preprogrammed MicroSD/SD Card features extensive coverage of more than 17,000 bodies of water across the U.S. and premium quality map data provided by NAVTEQ. More than 400 of these maps are available in HD with 1' contours consistently at all depths. All Garmin LakeVu HD Maps include shoreline with dock outlines, fishing areas, campgrounds, boat ramps, marinas, streams, channels and more. Underwater cartography for structures such as riverbeds, roads and underwater bridges are also displayed in this highly detailed product. The Garmin LakeVu HD Freshwater Lakes Maps MicroSD/SD Card is preloaded with highly detailed LakeVu HD maps, complete with 1' contours, in our new echoMAP 50s and 70s units and included it with our new GPSMAP 547, 547xs, 741, and 741xs units.