Stainless Steel Outer And Inner. Powder Coated Finish. Double Wall Construction For Insulation Of Hot Or Cold Liquids. Snap-On, Spill-Resistant Thumb-Slide Lid With Rubber Gasket. Due To Vacuum Insulation Technology, Capacity Is 18 Oz. With Lid On. Non-Slip Bottom. Meets FDA Requirements. BPA Free. Hand Wash Recommended.