Stainless Steel Outer And Inner. Stainless Steel Tumbler With Handle. 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.