Our White Poly Mailers 10 x 13 100 Pcs has been destructively tested and has the characteristics of waterproof puncture resistance and tear resistance. Self-seal adhesive closure strong adhsion it is really easy to use just tear off the tape packaging when you put the items in it White outer surface & black inner layer provides confidentiality. 10 x 13 Great size for books clothing stuffed toy and any small-medium stuff. Lightweight material and 100 pieces it perfect mailer for your online-sales business needs and cost effective for shipping!