BCW Current Comic Book Extenders - (5 Pack) Comics, Comic Books Archival Storage Collecting Supplies Helps prevent yellowing - Slows the Aging Process 200/Pack Absorbs and Neutralizes Contaminants in Comic Book Pages 10 mil thick sheets and Coated on 2 sides Only two sheets per book are necessary! Size - 6 1/2 x 10 1/2 ** Certified Acid Free - Independent Lab Tested