#1 7.25x12 Poly Bubble Mailers. Usable Space: 7.25" x 11". Surface made from durable premium poly. Interior padded with advanced low-density polyethylene 1/8 bubble to provide extra protection during transit. Simply peel and fold over to seal each package safely and securely. Extra large self-seal flap for full coverage. Highest quality poly bubble mailers made in the U.