13718.1 Double Window Confidential Envelope 8 7/8 x 4 1/2″ QTY 250 13718.1 Double Window Confidential EnvelopeSize 8 7/8 x 4 1/2″ The double window design clearly shows return and destination addresses. 24 lb. White wove stock. Security Pattern Inside Both windows are 3 3/4 x 1″ Space between windows is 11/32″ Top window is 17/32″ from top 7/16″ from side Bottom window is 1 19/32″ from bottom 7/16″ from side Seals securely when moistened.