Stainless Steel Outer And Inner. Double Wall Construction For Insulation Of Hot And Cold Liquids. Screw On, Spill-Resistant Lid. Wide Mouth Opening. Vacuum Insulated. Antimicrobial Properties Built In To Protect The Product. This Product Does Not Protect Users Or Others Against Bacteria, Viruses, Germs Or Other Disease Organisms. Keeps Drinks Cold Up To 24 Hours And Hot Up To 12 Hours. Hand Wash Recommended. BPA Free. Meets FDA Requirements.