Small pack self-seal 2.5 Mil 6" x 9" White Shipping Mailers Envelopes are the perfect packaging material to protect your products from moisture during shipping while also setting your business apart with a clean white style. Just add your custom label. White Mailers are Moisture resistant, Puncture resistant, Tamper evident and Tear resistant. The inner lining is silver which further protects the contents of your mailer. 6 in x 9 in .0025 Plastic mailer envelopes are commonly used for shipping a wide variety of individual goods like paper work, small books, apparel, accessories, fabrics, and more.