We were looking for a simple method of keeping our sand paper organized. We went to our local office supply store and found an expandable file (accordion file). Most are made of cardboard, but the one we bought was made from plastic. We figured it'd last a little longer. We added labels where appropriate and put our sand paper into each slot as required. It's easy to carry around, too.
Sand paper storage
Labels make the different grits easy to find.
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