The Business Source T-1 82 Packing List/Invoice Enclosed Adhesive Envelopes are designed for efficient packing and shipping processes. Measuring 4.5" x 5.5", these envelopes are red and black in color, making them easily noticeable. The adhesive closure ensures secure attachment to packages, providing a convenient way to include important documents such as packing lists or invoices. Ideal for business and industrial use, these envelopes by Business Source offer a reliable solution for organizing and identifying shipments.