Open End Catalog Envelopes, 9″ x 12″, 25#, White Paper/Poly/Paper, Smooth Finish, Center Seam, Peel & Seal (Box of 500). 9″ x 12″, Open End Catalog Envelope, No Window, Dura Print, White Paper/Poly/Paper, Smooth Finish, Center Seam, Flap Down, Kwik-Tak, 500 Qty / Box, 500 Qty / Ctn, 19.5 lbs.