OEM Quality Park Plain Expansion Envelopes, available in a carton of 100. These regular-weight envelopes provide superior protection for mailing bulky items that are not too heavy, serving as an ideal alternative to costly boxes or cartons. Made from DuPont Tyvek, they are designed to resist ripping, tearing, and puncturing, offering a much stronger and more secure option than traditional paper envelopes. The water-resistant and moisture-resistant features ensure your items stay protected during transit.