Jiffy Tuffgard Premium Cushioned Mailers are made from puncture-resistant, water-resistant, tamper-resistant poly with a clean, white textured surface for secure label application. Heat-seal seams will not burst. Mailers have a 3/16" high, Barrier Bubble layer for maximum cushioning. Use easy closure to seal. Simply peel away the liner and seal. Mailers are lightweight to save on postage.