Stainless Steel Outer And Inner. Powder Coated Finish. Double Wall Construction For Insulation Of Hot Or Cold Liquids. Keeps Drinks Cold Up To 24 Hours And Hot Up To 8 Hours. Screw-On, Spill-Resistant Lid with Straw Hole and 12" Straw. Vacuum Insulated. Meets FDA Requirements. BPA Free. Hand Wash Recommended.