28 x 22 x 1/4" White Jumbo Fold-Over Mailers. These one-piece Jumbo Fold Over Mailers are great for oversized flat items like portfolios, maps and blue prints. Mailer fully opens for easy packing. Simply lay product on the flat mailer, fold in and seal with tape. Attractive 200#/ECT-32-B white corrugated construction makes an impressive presentation.