The Harmony Chart Case was designed with the paddler in mind. It's made of premium non-glare frosted vinyl that can be marked on with dry erase marker but it will not lift photocopy ink from your documents. Its crisp fold over closure is durable and seals easier than conventional press lock closures especially with cold fingers. The stiff sides make the case easier to handle and charts easier to read. Finally, the corner-mounted swivel clips make it easily attachable to canoe, kayak or raft. Fits standard 11 x 17 paper.