Stainless Steel Outer And Inner, Double Wall Construction For Insulation Of Hot Or Cold Liquids, Snap-On, Spill-Resistant Flip Top Lid with Straw Hole and Matching 9 1/2" Straw, Vacuum Insulated, Due To Vacuum Insulation Technology, Capacity Is 22 Oz. With Lid On, Non-Slip Bottom, Meets F-D-A Requirements, BPA Free, Hand Wash Recommended