12 1/2” W x 19” L (50 Pack) – outside dimension and 12 3/8” W x 17 3/4" L – Inside usable dimension, Poly Mailers Self-Seal, with the cushioning of 3/16" bubble lining. Poly Mailers are with Tear Strip, 2.5 MIL Thick, puncture, water / moisture, tamper, and tear resistant. High strength seams will keep contents intact, even if over packed. The outer surface of the mailer is white, and the inner lining is silver. Labels, stamps, and ink adhere well. The price mentioned is for 50 Poly Mailers. There is no minimum order requirement. However, more than one case would get you a better shipping rate per box.