These refill pages are permanence engineered to preserve everyday photos for 200 Years.You get 10 Black Perma-Hinge Refill Sheets, plus 2 post extenders in each package.Archival album bindings need to be both strong and flexible. A completed album can weight up to 6 lbs. once mounting materials, photos and memorabilia are added. This album pages are 100 times stronger than average photo album pages. You can extend your album up to 40 pages in most cases.