Garmin Lakeview HD Charts G3Lakeview HD Charts G3 Coverage for more than 13,500 total lakes, with over 4,800 featuring 1 contours Auto Guidance technology quickly calculates a suggested route using your desired depth and overhead clearance Includes Depth Range Shading for up to 10 depth ranges, making it easy to view your target depth at a glance Shallow Water Shading highlights shallow areas at a user defined depth to help avoid hazards