OEM C-line Heavyweight Polypropylene Sheet Protectors offer a top-loading design, sealed on three sides for easy loading. There is no need to punch sheets, allowing you to load documents while the protector remains in the binder. These sheet protectors fit standard three-ring binders and are made from polypropylene material that provides safe, archival quality with no photocopy-transfer protection. The strong, reinforced binding edge prevents tears, ensuring durability even with heavy use.