Works with first class mail. White outer surface/Turquoise inner lining - Multi color printed Peacock design across both the front and back of each bag Unsurpassed Water & Tear Resistance - Superior side seams combined with Heavy Duty 100% Virgin polyethylene make these envelopes are highly resistant to water, punctures, and tears Pressure sensitive self seal with Anti Static Release Liner - Easy packing, tamper-evident, and super secure closure Light Weight & Time Saving - 100% recyclable