Sealed Air 37713 Sealed Air Jiffy Tuffguard Self-Seal Cushioned Mailers, 8-1/2x12, White,25/Ctn White polypropylene shipping mailer features a self-seal closure and a Barrier Bubble air cellular lining. Puncture-, tamper-, and water-resistant. Heat-seal seams. Lightweight Barrier Bubble air cellular lining.