Pendaflex Redrope Heavy-Duty Accordion File Pockets, 7" Expansion, Letter Size, Brown, Box Of 5 Pockets - For tough jobs, there are Pendaflex heavy-duty accordion file pockets. Besides the heavyweight front and back covers, these file pockets are designed with Tyvek gussets and reinforcement strips at key stress points to help keep your letter-size sheets of paper safe.