Bags are 100 % virgin, high clarity polyethylene film. All poly bags meet FDA and USDA specification for direct food contact. Bag is available in 1.25 mil to 4 mil thickness. Reclosable Bag, Flat Poly Bag, Slider Zip and Shopping Bags are type of Poly Bag available with Packaging Supplies By Mail and can be order in large quantities as well as are available in variety of sizes.They can be easily closed with heat sealers, scotch tape, or a stapler. PackagingSuppliesByMail.com carries all kind of packaging supplies needed for daily purpose as well as for industrial use.