The Mead #10 Envelopes are security printed with a white lining, making them ideal for everyday office use. With a size of 4-1/8″ x 9-1/2″ and a gummed closure, these envelopes provide a secure way to send documents and letters. Made of paper and weighing 0.44 pounds, this pack of 40 envelopes is perfect for ensuring the confidentiality of sensitive information. The rectangular shape and no window design make them a practical and reliable choice for all your mailing needs.