"The most breast-like nipple. Makes switching from breast to bottle and back again, easy. Breast-like shape for natural latch Soft silicone flexes and stretches like a breast Anti-colic valve, keeps air away from baby’s tummy Different flow rates, so baby can feed at the pace they need It’s also BPA free" 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 valve: 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 Flow rates: Tommee Tippee Natural Start nipples are available in varying flow rates, to keep up with your baby's growth BPA free: All Tommee Tippee nipples are BPA free for added peace of mind