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Archival Methods Onyx 8.5x11 x 2 Portfolio Box 8.75 x 11.25 Black Buckram / White Lining.

Box core is Kappa binders board 01 a bookmaking board with no glue between layers
Lined with 80 lb acid- and lignin-free paper
PAT tested and passed
Covered in library quality F-Grade Buckram poly-cotton with a moisture-resistant 100 aqueous acrylic coating
Adhesive is pH balanced and buffered