The Zero Lines map card is the starting point for building your own maps with AutoChart or AutoChart Live. You can begin creating your own, accurate and detailed maps of any fishing spot, even where contour coverage doesn’t exist.Anglers can purchase Zero Line Map Cards to view the AutoChart-created maps on multiple Humminbird units. Simply export the map from the program to the extra Zero Line Map Card and you’ll have multiple charts of your favorite fishing spots ready to view on a range of compatible Humminbird fish finders.For those with GPS-equipped HELIX G2/G2N Series models, or any SOLIX models, the Zero Lines card can record depth contours, bottom hardness and vegetation directly onto the card