Yes they do have cards for them and I think the best I can remember they cost me about $100.00 each for the midwest lakes. Having a H2O without the card is ok but its so much better with the card. I really need to sell both of my units since I got this Garmin I love it! AND SINCE MR BUGMAN WAS NICE ENOUGH TO DOWNLOAD ALL HIS CRAPPIE BEDS ON LOZ ON TO MY GARMIN I REALLY LOVE IT! Plus now I have all of Bugmans waypoints loaded from my Garmin to my computer.