EcoSwift Size #4 10 x 13 Poly Mailers Self Sealing Bulk Shipping Supplies Packaging Materials Envelopes Bags 2.35 Mil EcoSwift Size #4 10 x 13 Poly Mailers Self Sealing Bulk Shipping Supplies Packaging Materials Envelopes Bags 2.35 Mil Size: #4 Dimensions: 10" x 13" Thickness: 2.35 mil EcoSwift Self-Sealing, Peel and Stick Adhesive