These large 16x24" bags are heavy weight yet they are archival and uncoated. This 16x24" Poly Zip Seal Newspaper Pouch 4 mil Clear Envelope is water
resistant, thick, and completely inert. Size is 16"x24", zips along the
16" side. It nicely fits most older aged (civil war, etc) newspapers
flat (in reading position) up to 15.5"x23.5". In the home economics
world, they are popular to use for storage of household goods. They work
well for protection from moisture.