Bubble Mailers offer strong, air bubble protection. Ideal for mailing pictures, cassettes, jewelry & more. Tough outer layer provides stiffness & rugged durability. Water-resistant design is lightweight for postage savings. No. 7 mailers feature a pressure-sensitive strip closure. Simply peel away liner & seal. Envelopes are preprinted with “To” & “From” address lines. Each contains a high percentage of recycled paper.