Book of No. 10 envelopes are conveniently packaged in a bound book format containing 36 envelopes. Envelopes stay together for travel or store neatly in desk drawer. Design features a security tint for privacy and easy-to-seal flap. Removable sealing strip provides clean, quick seal without the use of moisture. Pressure-sensitive gum forms a permanent bond. Made of 24 lb. white wove stock.