I have not used this very much, maybe 6-10 times? It has a top clear pocket to put maps in. The main compartment in it is expandable by an outside zipper. Inside the main compartment is a mesh pocket. Uses 4 strong magnets, and also has a back up strap to go around your tripple.
dimensions are 14"x10"x3" expands to 14x10x6. Comes with the origional clear vinyl rain cover, and a zippered plastic bag you can put stuff in on the inside, so nothing ever gets wet.
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Asking for $50 canadian sells for 60usd on helmet harbor.