Leak-proof silicone seal around straw opening coupled with a spill-proof valve inside means no more messes BPA-free Soft-grip bottom prevents slipping and tipping Fits most car cup holders Top-rack dishwasher-safe lid and body; straw twists apart for easy cleaning This product contains Stainless Steel (Iron, Chromium, Nickel, Manganese), Octamethylcyclotetrasiloxane