Premium Quality Park Tyvek Open-End Expansion Envelopes - Durable Waterproof Mailing Solution for Documents, Photos & Legal Papers - Perfect for Shipping, Mailing & Secure Document Storage

Expansion Envelopes with heavyweight Tyvek offer superior protection for mailing bulky items that are not too heavy. They are ideal replacements for costly boxes or cartons. Design features an open-end style and convenient Flap-Stik closure. Envelopes with DuPont Tyvek won't rip, tear or puncture. They are much stronger and more secure than traditional paper envelopes. These 18 lb. expansion envelopes are water-resistant and moisture-resistant. They are easy to use. Simply peel and seal.