Each one is made out of smooth, high quality, 28 lb. paper and features a straight flap with a reliable, easy-to-use metal clap closure as well as an optional gum closure for additional reinforcement. With their sleek and classy jet black color, these envelopes will make any mailed item look both unique and professional. Their size makes them ideal for standard and slightly larger sized sheets of paper without bending or folding. Use them to send documents, files, forms, and more! Details:Black10" x 13"28 lb.Available in multiple countsSmooth finished