Description Envelopes expand to provide lightweight, inexpensive shipping for bulky items. Expandable envelopes are made of puncture, tear and moisture-resistant DuPont™ Tyvek® material. Envelopes made with Tyvek® are half the weight of heavy duty paper envelopes, so you save on postage with each mailing.
Product Details Basis Weight 18 lb Tyvek Color Family White Color(s) White Envelopes/Mailers Closure Redi-Strip® Adhesive Envelopes/Mailers Exterior Dimensions 10 x 13 Expansion 1.5" Exterior Material(s) DuPont™ Tyvek® Flap Type Square Footnote 1 DuPont™ and Tyvek® are registered trademarks of DuPont™ Footnote 2 Tyvek® basis weight is measured in pounds per 500 uncut 24" x 36" sheets of Tyvek® material Format/Border USPS First Class Mail Format & Border Global Product Type Catalog Envelopes Opening Open End Post-Consumer Recycled Content Percent 0% Pre-Consumer Recycled Content Percent 0% Preprinted Message First Class Mail Product Biodegradability in Days 0 Seam Type Center Security Tinted No Special Features USPS First Class Mail—Heavyweight 18 lb Tyvek® Total Recycled Content Percent 0% Trade Size #13 1/2