When archival-quality mounting is needed, Elmer's 100% cotton rag foamboard really performs. Constructed with pure, naturally white cotton fibers, it contains no lignin, alum, or harsh chemicals to discolor your work.
This cotton rag foamboard is easy to cut, it has a uniform surface, and it features a "memory core" that resists dents.
Elmer's 100% Cotton Rag Foamboard is
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® Elmer's is a registered trademark.