100% pure food-grade silicone transition cups. Lids can be removed easily so please monitor curious toddlers! Microwave, dishwasher & freezer safe. Straw is attached to the lid and has a one way valve to help prevent leaks. Soft & flexible, yet durable with removable handles. 6 oz capacity for water, milk, smoothie or juice. Flexible silicone straw is non-toxic and gentle on gums and teeth. Allows for drinking from different angles with a bent straw.