3.15 mil thick! 50% thicker than most! Unsurpassed Water & Tear Resistance - Superior side seams combined with Heavy Duty polyethylene make these High Quality envelopes highly resistant to water, punctures, and tears * Pressure sensitive self seal - Easy packing, tamper-evident, and super secure closure * Light Weight & Time Saving - Lower shipping costs combined with faster shipment preparation equal big savings over other packaging option * 100% recyclable *Color may vary due to device screens and lighting differences