Pigeon peristaltic nipples are developed based on 3 key steps of sucking.
-the lips and tip of tongue grasp the nipple and areola
-the nipple is held tightly inside the oral cavity
-the undulating motion of the tongue compresses and expands the nipple
-infant swallowing transfers the milk down the esophagus.
This size is recommended from 9+ months. It is recommended to replace nipples every two months.