C-Line 13-Pocket Expanding Files are made of acid-free, archival quality polypropylene with a button and elastic closure to hold coupons and other small items inside. These expanding files are the perfect solution for holding, protecting and organizing notes, cards, valuable coupons and more. C-Line 13-Pocket Expanding Files have 12 pre-printed label inserts for quick view organization, making them an all-around filing solution for home, office or school. For over 60 years, C-Line has been a leading manufacturer of office supplies, with a product line that features storage, identification and organization products, including an assortment of new products to help you store, protect and organize your most valuable materials.