Save time with this single window #6 envelope by having your return address imprinted and even have you company logo added at no additional cost. This single window envelope has a gummed flap and seals securly when moistened. Envelope size 6 1/2 x 3 5/8 Window size 4 1/2 x 1 1/8 Window placement 7/8 from left and 2 inches from top.