When you create a waypoint on your Humminbird, it is automatically saved in the unit’s memory, not on your map card. After removing your LakeMaster map card, the waypoint will still be in the unit, not on the map card. You may want to invest in a blank SD card to back up your waypoints so you’ll have them in case something happens to your GPS unit. Saving waypoints to a blank SD card will also allow you to move them to a computer program, or another GPS. Do NOT use your LakeMaster card to save waypoints. You could corrupt the map data and void the warranty.