I've got a number of smaller maps that have been printed off the computer. They are on 8 1/2 X 11 sheets. I needed a way to make 'em waterproof. Took my vacuum food sealer and using the clear side of the bags, sealed on end, slid the map in and then hit the vacuum seal on it. Puts them in a nice waterproof package that you can keep rolled up to store easy. It sure beats trying to use the laminating sheets. Most USGS topo maps are available on-line and smaller versions can be printed for free. They work good if you're on water that you aren't familiar with for landmarks to navigate with.