Premier Coastal Charts Industry-leading coverage. clarity and detail with updated coastal charts that feature integrated Garmin and Navionics content Auto Guidance¹ technology quickly calculates a suggested route by using your desired depth and overhead clearance Includes Depth Range Shading for up to 10 depth ranges. enabling you to view your target depth at a glance Up to 1 contours provide a more accurate depiction of the bottom structure for improved fishing charts To give a clear picture of shallow waters to avoid. The Shallow Water Shading allows for shading at a user-defined depth