Survivor® 12 x 16 x 4 DuPont Tyvek Expansion Mailers with Redi-Strip® Closure - Expansion - 12" Width x 16" Length - 4" Gusset - 18 lb - Peel & Seal - White - Tyvek - 50 / Carton

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. Envelopes feature open-side style and convenient Flap-Stik closure. Envelopes made with DuPont Tyvek won't rip, tear or puncture. They are much stronger and more secure than traditional paper envelopes. These 18 lb. envelopes are water-resistant and moisture-resistant. They are easy to use. Simply peel and seal.