Our 40" x 50" 4 Mil flat poly bags are heavy weight plastic bags that provide protection for industrial parts and tools. Also great for use as freezer bags! All 40x50 4mil polybags are made from low density polyethylene and can be recycled. Our flat open top 40" x 50" .004 plastic bags feature impressive clarity and make storage and organization simple for industrial, food service and medical industry applications. These heavy weight plastic lay flat 40 inch by 50 inch bags can be sealed by using twist ties, bag tape or by heat sealing, and they meet FDA requirements for use in food packaging and storage applications.