18 x 23 White Flat Tyvek Envelopes 100/Case

These envelopes are crafted from 14 lb. olefin, making them ten times stronger than regular paper envelopes. They come with a convenient self - seal closure. You can choose between plain designs and those with First Class printed borders.

Using these envelopes is easy. Just open the self - seal flap, put your items inside, and seal it shut. For best results, make sure the items fit well without overstuffing as it might affect the seal. When it comes to storage, keep them in a dry place away from direct sunlight. If they get dirty, you can gently wipe them with a damp cloth. That's all there is to it, and you're ready to use these tough envelopes for your mailing needs.