The superior durability of the Heavyweight Polypropylene Sheet Protectors make them C-Line"s most popular top-loading sheet protectors. Reinforced binding edges make it easy to store frequently used 8 1/2" X 11" documents safely in binders with no hole punching necessary. Non-stick and acid-free, the heavyweight sheet protectors provide archival-quality storage. The clear finish allows for easy viewing of your important letter-sized documents. 50 Sheet protectors per box.