3-5/8" x 6-1/2" ( 3.625" x 6.5" ), Regular Envelope, No Window, Western Sulphite, White Sulphite Paper, SFI Certified, Vellum Finish, Side Seam, Flap Down, Remoistening Seal, 500 Qty / Box, 5000 Qty / Ctn, 4.5 lbs. per Box