The Munchkin LATCH Nipples are designed to help you reach your breastfeeding goals. Experts agree that a better latch eases the transition between breast and bottle, and back. That's why our accordion nipple pumps and moves just like the breast, stretching back to your baby's soft palate for a correct latch. </br>Features: </br>Better Latch - accordion-style nipple on the LATCH bottle stretches like the breast, helping baby LATCH easily and corectly. Like the breast - mimics mom by releasing more breast milk as baby pushes against the nipple's base. Less colic - accordion-style nipple flexes as baby moves their head while allows baby to maintain their latch, thus decreasing ingestion of air. Top rack dishwasher safe. Medium-flow, silicone nipples.