Thanks to the Nuby valveless, leak resistant spout, your baby will find the transition from bottle to cup easier than ever. Since it is made from the same safe, soft silicone material as Nuby nipples, your child is comfortable with the feel and function of these No-Spill spouts. While the unique contour shape easily fits their small hands, the spout is still gentle on your child's tender gums and emerging teeth. Plus, it's all BPA Free.