Innobaby's Sippin Smart fez flow stainless straw sippy allows fez drinking in any position with its fez flow design and personalization option with its design it yourself stainless cup insert. Type 304 stainless cup is durable and easy to clean and provides double lined insulation when used with the plastic cup. Fez flex smart straw is designed to be leak resistant even when it is flipped and offers a continuous flow in any position with its weighted stainless ball. Fez transition comfort straw is designed to be durable and comfortable with its bubble shaped curve to prevent slipping while sipping and making transitioning to a straw cup easier. Fez grip lid with leak-proof silicone seal makes it 100% leak-proof. Silicone air release valve prevents liquid overflow and guarantees easy flow. Designed with a wide cup opening and curved base, Sippin Smart fez flow straw sippy is easy to clean. Set Includes 1 10 ounce cup with handles, 1 8 ounce stainless cup insert, 1 silicone stainless cup ring, 1 fez grip lid with flip top cap, 1 silicone ring for leak-proof seal, 1 silicone smart straw with weighted ball, 1 straw cleaning brush. BPA , Phthalates , PVC , Lead Free. Top rack dishwasher safe.