The 50-pack of FI57 5 x 7" Interleaving Folders from Print File contains 3-mil polyester enclosures that store negatives and protect them against dust and fingerprints. Each folder has a single fold on the short side, remaining open ended on the other three sides. Once you have your negative in a folder, you can further protect it by slipping the folder inside a compatible NP57 envelope.
UPC: 029368079305