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If you have Maine POIS and charts, that means you have the north american maps loaded. What you need is the Garmin BlueChart G2 canadian map / charts. ( not G2 vision or G2 HD )
You can get the pre loaded Canadian SD card here, http://amzn.to/2af6ybC
Once inserted you would just restart your device and then go into settings, map info and select the new canadian Maps~
The Amazon link I sent you will save you 56$ over the cost of the same exact card / map from Garmins website https://buy.garmin.com/en-US/US/maps/on-the-water-maps/bluechart-g2-hd-interactive-maps/hxca015r-canada-g2-hd/prod37704_010-C1019-20.html
If you have further questions, let me know.
I strive to provide great service, and greatly appreciate a 5 star rating clicked and submitted when you are satisfied.. I always answer follow up questions.Dustin S.Senior Technician and Network Switching Systems Operator / Maintainer.