That is correct John. You need a chart that has a file on the card called nTag. If you have that file you can get the freshest data updates however there is a charge for the updates.

Navionics provides you with 1 full year of updates at no charge when you register your chart with them within 60 days of purchase. Anything beyond that or to renew there is a charge for people who have charts with the nTag file on them

-Lawren