This slim-line chartplotter flush-mounts easily in your boat and boasts an ultra-bright 5” QVGA display. Also sports a built-in, satellite-enhanced worldwide basemap and simple, straightforward buttons and menus. You can add the optional BlueChart® g2 Vision SD card for even more enhanced features. Add SonarWhere applicable, the sounder version, GPSMAP 520s, comes with a powerful dual frequency transducer that clearly paints depth contours, fish targets and structure whether you’re fishing in freshwater or off the coast. The 520s is also CANet™ compatible, so you can share sounder data with another chartplotter on your boat.Add Extras with BlueChart g2 VisionWith the optional BlueChart g2 Vision SD card, you can add a whole new dimension of exceptional features to your chartplotter.3D mariner’s eye view or fish eye view provides you with a 3-dimensional perspective of map information, both above the waterline and below it. High-resolution satellite images and aerial photographs help you orient yourself in unfamiliar areas. Auto Guidance technology searches through all relevant charts to create a route you can actually follow — one that avoids obstacles, shallow water, buoys and other obstructions.