These colorful pocket envelopes are ideal for storing Hygloss flashcards and learning cards. You can also mount library pockets on the wall or bulletin board and use for attendance charts and job charts. And of course, the colorful pockets are terrific for library management. Library pockets are made of durable text stock paper. They are acid free, fade resistant and accept all mediums. 30 pockets each, bundle of 3, 90 pockets total