With the Medela Calma feeding system, your little one drinks just like at the breast. The Calma is based on the natural sucking rhythm of a baby. Babies control the flow of milk by moving the tongue up and down and have to create a vacuum with the Medela Calma to keep the milk flowing. This makes it easy to combine breastfeeding and bottle feeds. Calma comes with a 150 ml bottle. Suitable from 0 months. Color: transparent / yellow.