Now, switching from bottle to breast is easy. Designed exclusively for breastmilk feeding, the Calma® encourages an easy transition by simulating natural feeding behavior. Features a flow control valve that allows baby to control the flow of milk and milk only flows once baby creates a vacuum. The design permits your baby to feed, pause, and breathe just like natural breastfeeding. One-size nipple handles all stages of breastfeeding. Set includes one 8-ounce/250ml bottle, one-stage nipple, one cap, and two lids. Imported.