Stainless Steel Outer And Inner. Smooth Rubberized Finish. Double Wall Construction For Insulation Of Hot Or Cold Liquids. Vacuum Insulated. Screw On, Spill-Resistant Lid. Keeps Drinks Cold Up To 24 Hours And Hot Up To 12 Hours. Cork-Look Rubberized Base Protects Surfaces From Heat And Scratches. Meets FDA Requirements. BPA Free. Hand Wash Recommended.