... courier bag, express bag, and mailing bag, express delivery bag, mailer bag, post envelope: materialLDP and HDPE coextrusion materialthickness0.05 ... quality certification, SGS certification.2) Printing: 1-10 colors, both printed by copperplate printing and non-printed plain, as ... are just for your reference, customized size, designs, logo printing, packaging, etc are welcomed.our advantage:1)quality: ...