For people who fish in lakes that have a lot of standing timber, river sections etc. a good mapping card can be invaluable. Knowing that you are in the channel can be the difference between making it back in one piece and punching a big hole in your rig, or worse. A good mapping card is also very valuable for for excluding or including areas in your fishing day. If for instance you get on a pattern where you are only catching fish in a certain depth, or on drops, you can easily and quickly find and fish areas that match your pattern. If you go and fish a new lake, the map card can cut your learning curve way down.

There's a chance you may not need it, but it's another tool that can help you be more productive on the water, when it counts.