Air-Kraft Hefty Express 6"x10" Bubble Padded Mailers, #0 - 25 Pack Uniform Astro-Cell air-cushioned lining outperforms other air cushioned shippers in puncture testing Fin bottom and sides improve impact resistance Low-friction, air-cushioned, poly lining provide quick product insertion and removal Convenient self-seal make our mailers easy-to-use with secure closures