Envelopes offer a ruled format on one side for interdepartmental routing. Holes allow visual acknowledgment of contents. Interdepartmental envelope design features a string-and-button closure and standard style with five columns: Date, Deliver To, Department, Sent By and Department. Envelopes are made of 28 lb., brown Kraft stock. Quality Park Standard Style Inter-Department Envelope - Interoffice - 10in. x 13in. Made by Quality Park.