Transit Sacs are reusable, long-lasting, and are available in two fabrics-nylon and laminated nylon and several colors to make mail sorting easier. Approved by the U. S. Postal System, Transit Sacs save you 96% annually on envelope costs and 37% on postage. The zipper closure keeps contents secure in transit and can be combined with a combination lock or a security seal that loops through the zipper to ensure the mail remains confidential. Available in three sizes, flat Transit Sacs are ideal for small parcels, bulk mail, report files, and catalogs. A see-through window on the bag is perfect for a shipping information, business card or company identification. Great for banks, retail stores, hotels, law offices, and government agencies. One side/ one color/ one location imprint at no charge. Embroidery available for an additional charge.