This listing is for a pack of 100 Supersafe Museum Grade Currency Sleeves for Large Bills 3 1/2" x 8" (MG450). Supersafe MG (Museum Grade) series Currency Sleeves are made from 4 mil Mylar. The Mylar polyester film makes these Currency Sleeves ideal for long term storage. These bill holders open on the left and right and also can be opened at the top for easy insertion. The top folds over for added protection. Each Currency Sleeve holds a single bill or note. These Currency Sleeves are new from our inventory.