Pendaflex Expanding File Pockets, Letter Size, Redrope, 3.5" Expansion, Reinforced with DuPont Tyvek Material, Redrope, 25 per Box (1524E-OX) Standard expanding file pockets with double-thick fold-down front, Tyvek reinforced gusset top and Manila lined back. Double-thick front folds down for easy access to documents. Single pocket expands up to 3.5". Tyvek reinforced gusset tops resists tearing. Red fiber with Manila lined back.