2013 plastic courier envelope self-seal open made of LDPE co-extruded Material: LDPE film of white outside and black inside Mail ... ;Quotation: Depends on the material, size, thickness, printing color, freight and quantity of the bags;Advantage: Professional manufacturer, ... ;Moisture proof;Clean and easy to use;Lightweight for postage savings.Remarks: Customized design, size, color and printing are ...