Pura’s design team came up with the first and only 100% plastic free straw top. It is made of 100% medical grade silicone and is composed of two pieces, making it easy to clean and easy to use. If the straw attachment is removed from the top piece, your child can tip the cup to drink. Helping them learn the process of using a straw upright cup. The tip of the straw has a soft valve that makes this straw top completely leak proof! All of Pura’s tops are interchangeable between cups.