Cardboard Envelopes & Mailers | Standard Solid Board | 234x334mm
Mailer Envelopes/Cardboard Envelopes - A4. 100/Pack - Rigid Mailer A4 for Book Packaging DVDs etc The Ideal Capacity Book Mailers Expand to Fit 50mm Thickness, Large Letter Size at 25mm. : Amazon.co.uk:
460 x 330mm RIGID FLUTED PRINTED CARDBOARD ENVELOPES