Natural latch: Our bottle nipples are shaped to encourage a natural latch, reducing air intake and preventing nipple confusion when switching between breast, bottle and back again., Anti-colic: Tommee Tippee Natural Start nipples feature an innovative anti-colic valve which reduces air ingestion, helping to reduce the symptoms of colic., Pace feeding: The soft silicone nipple flexes and stretches like a breast and allows your baby to feed comfortably at their own pace., Self-sterilizing: Tommee Tippee Natural Start bottles can be easily self-sterilized in the microwave in just three minutes., 100% leakproof: When the screw ring, nipple and cap are all secured, your baby bottle is completely mess-free and leakproof, even if it’s turned upside down or shaken