No #1 Glassine Envelopes. Size: 1 3/4 X 2 7/8 “”. Pkg. Of 250. All envelopes are made from the best, transparent virgin 30# glassine to assure maximum visibility. Ungummed, folded down flaps with strong seams, using anti-tarnish adhesive which will not affect contents. Smooth cut edges to insure that perforations will not be harmed.