We use these almost daily in our historical society. They protect our photos and important documents. I've been purchasing them in large quantities since 1999. They are very useful and helpful.I used to be able to get a box and then get a box free. But I no longer find those offers. Why not? The store should restore that special purchase. It would be a money saver for those of us in the not for profit industry. With the use of sheet protectors we can allow more people to see and view these important documents that we have in our collection.