For thick stacks of paper. A pack of paper feels really solid. Strong staples are required to staple an entire stack of paper. That's why you need Bostitch No. 3-10 staples, made from high-strength steel that doesn't bend easily. All staples are strong enough to penetrate a large stack of standard-density paper all the way through, bending only slightly at the very end to securely bind all the sheets together. These staples are universally applicable due to their standard width. So take a strip of staples, load it into the stapler, and press it down to securely staple all documents together. Furthermore, the strength of these staples ensures that you won't waste any staples. Staple thick stacks of paper together with ease!.