# 10x13 Envelopes Open End-White Catalog Envelopes 100/Box (10x13) Great mailing envelope for lots of use. Ideal for mailing documents, catalogs, direct mail, promotional material, brochures and more. Open end closure. Moisture activated gummed seal These are heavy 28 lb. white stock with Moisture activated gummed seal. 10" x 13" 100 count