Business Source 28 lb. White Catalog Envelopes - Catalog - #10 1/2 - 9" Width x 12" Length - 28 lb - Gummed - White - Wove - 250 / Box Durable, all-purpose mailing envelopes are ideal for mailing documents, catalogs, direct mail, promotional material, brochures and more. 28 lb. opaque white wove construction delivers privacy of contents. Open-ended style allows you to easily insert and remove items. Moisture-activated, gummed flap provides a secure seal. 9" x 12" size is perfect for documents without folding.