Look at the current map on the Navionics website's Web App.
If it shows the markers, you can get a better map card at a discount with the Navionics Update version.
You use your current card to activate it and it becomes the 2GB version of Navionics+.
It has no maps, you choose what locations to download to the card including the Sonar Charts map layer.
Humminbird Helix 12 CHIRP SI, 1198c SI, 1198c SI, ONIX 10 SI NT, Helix 7 CHIRP SI GPS G2, 360, RC-1