Here’s the professional way to send flat but bulky materials- pamphlets, brochures, sales literature, booklets, annual reports, magazines, or catalogs. The flap, usually rectangular, opens as a booklet style flap on the long side for easier filling. Available with moistenable flap, some with self-stick Peel & Seal. This standard envelope, is great for everyday business, and is the least expensive white paper, but isn't "cheap" looking. These envelopes are made from 24lb paper, measure 6 x 9 inches and are available in a range of styles and sizes; choose the envelope that fits your needs.