100 Pack - 10 x 13-inch Poly Mailers Envelopes Bags with Self-Sealing Strip White Shipping Bags 100 of 10" x 13" Plastic Shipping Bags Heavy-Duty Weather, Tear, and Puncture Resistant - wont bust or break open, even if over-packed. Pressure sensitive adhesive provides a high strength durable closure, water and dirt resistant High-efficiency mailers are perfect for shipping a wide variety of non-fragile items. White outer surface/Silver inner layer provides confidentiality