SAFETY INSTRUCTIONS
CAUTION
No one navigational aid should be relied exclusively for the safety of vessel and crew. The navigator has the responsibility to check all aids available to confirm position. Electronic aids are not a substitute for basic navigational principles and common sense.
Digital charts cannot replace official nautical charts.
Digital charts are intended as an aid to navigation. Position should always be checked against nautical charts, as well as other aids to navigation.
Digital charts cannot replace the radar.
Digital charts can only show own ship's position relative to a chart feature (coastline, lighthouse, etc.); they cannot show other vessels, as does the radar. Digital charts can never replace the radar.
Handle chart/memory cards carefully.
The chart and memory cards are weak against heat and magnetic material. 
Keep cards away from heat source.
Keep cards away from magnets and magnetic material. 
Replace cards in their protective cases after use.
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