Free of BPA. Easily alternate between bottle & breast. The 5 oz Breastflow bottle is ideal for newborns and young infants and includes a Stage 1, slow flow teat.Breastflow is the only feeding system that requires both suction and compression, just like breastfeeding. The teat is designed to mimic the breast so baby can latch on and to encourage the same mouth and tongue position as breast feeding. The double teat system requires both suction and compression, just like breast feeding and baby controls the flow of milk. It's the bottle most like breastfeeding. This Natural Transitions Manual Breast Pump provides for comfortable, quiet and efficient pumping. Adjustable swivel head Unique shield design Lightweight, compact design comes with two 5 oz bottles with sealing discs for storing BPA-free Suitable from Birth