Adhesive Seal. High Impact Bubble Cushioning. Easy to close with adhesive seal. Lined with 3/16 inch bubble cushioning to protect & ship contents, and fragile items safely. Lightweight, helps reduce shipping costs.These bubble mailers combine the tear, weather and puncture resistance of a courier envelope with the cushioning of a duraliner bubble lining. Each mailer is made from 100% polyethylene. Shipping/postage costs is lower than many alternative packages. The white outer surface is ideal for high-quality printing.