9.02 x 6.38 " Yellow Board Back Peel & Seal 74lb Paper / 600gsm Grey Board Envelopes
Amazon.com : Triplast 20 x A5 C5 Manilla Hard Board Back Envelopes (229 x 162mm) - Cardboard Backed Please Do Not Bend Envelope with Peel & Seal Strip - Perfect for Mailing,
Amazon.com : Blake Purely Packaging C5 (A5) 229 x 162 mm Board Back Pocket Peel & Seal Envelopes (5112) Manilla - Pack of 125 : Office Products