These Tyvek® envelopes provide superior puncture, tear and moisture protection. They are constructed from 14 lb. olefin. These envelopes are ten times stronger than paper envelopes. They feature a special seal that once broken, the word "OPENED" appears in red on the flap.

These Tyvek® envelopes provide superior puncture, tear and moisture protection. Features: Constructed from 14 lbs olefin Ten times stronger than paper envelopes Features self-seal closure Available in plain and first class printed borders

These Tyvek® envelopes provide superior puncture, tear and moisture protection. Features: Constructed from 18 lbs olefin Ten times stronger than paper envelopes Envelopes expand to hold bulky items Features self-seal closure

Features: Self-Seal Envelopes make sealing envelopes fast and easy No moisture needed to seal! Simply peel off tear strip and seal Tear off strip keeps adhesive free from dust for a longer shelf life Constructed from durable 40 lb. paper stock Sides expand to hold bulky items End loading

These Tyvek® envelopes provide superior puncture, tear and moisture protection. Features: Constructed from 18 lbs olefin Ten times stronger than paper envelopes Envelopes expand to hold bulky items Features self-seal closure