Survivor® 10 x 13 x 1-1/2 DuPont Tyvek Expansion First Class Border Mailers

First Class Mail - 10" Width x 13" Length - 1 1/2" Gusset - 18 lb - Peel & Seal - White - Tyvek - 100 / Carton. Made with durable yet lightweight, 18 lb. DuPont Tyvek that's tough enough to resist punctures, tears, moisture and chemicals for long-lasting performance. Gusseted sides that expand up to 1-1/2" to accommodate bulky items.