10x13 Self Seal Catalog Envelopes-Color Bright White Large Envelope-10 x 13 Open End-Pck 35 (White) Size: 10"x13" ,Envelope Closure: Self-Seal,Opening: Open end flap Paper weight: 28 lbs.Envelopes is laser/inkjet compatible Comes 35 in Pck They are strong, hold very thick magazines, catalogs, and mailings, and seal quickly and with very little effort.