Stand & fill expandable bottom. Patented maxlock: track design for an extra strong seal. Click/zips and clicks closed: so you know the seal is secure. Expandable bottom: makes it easier to stand & fill. Helps prevent freezer burn: keeping food fresher longer. Certified 100% recycled paperboard. This carton is made with 100% recycled paperboard that can be recycled again after your use. Recycle Hefty Brand Bags when clean and dry at participating retailers in the United States. Hefty.com.