Astrobrights cardstock features assortments of colored cardstock that combines standout color with cardstock strength that won't let you down. 65 lb. cardstock holds up to the frequent handling and rigors of postal machines. Acid-free material prevents it from yellowing or crumbling to maintain its bright appearance over time. Multipurpose paper is compatible with laser printers, inkjet printers and copiers. Letter-size paper is perfect for menus, posters, sale signs, presentations and more.