Columbian CO325 6x9-Inch Booklet White Envelopes, 500 Count A durable ALL-PURPOSE mailing envelope. Ideal for mailing documents, catalogs, direct mail, promotional material, brochures and more. Open side closure for easier insertion and retrieval of contents. Durable 24lb white wove material. Moisture activated gummed seal. 6" x 9" 500 envelopes