Digi-Clear Windows 3180 Laser Safe Window Envelopes, #10 4-1/8 x 9-1/2", Side Seam, Box of 500. White sulphite 92 bright smooth finish window envelopes with two side seams. Window film performs under high temperatures. Stays clear without shrinkage, wrinkling or distortion. Readability and scanability of addresses and barcodes is better than any other existing window film. Manufactured with a unique paper that's specifically designed to reduce image distortion and hold toner better. Fully gummed flaps require moistening. Window size 1-1/8 x 4-1/2" - 7/8" left, 1/2" from bottom.