SofTouch™ nipples feature a unique valve with an air ventilation system (AVS™) to enable smooth and comfortable sucking. The Anti-Colic, advanced air vent system reduces intake of gas which causes colic.
The bubbles that appear in the bottle form as a result of this system, and are a sign that the ventilation is working correctly.
If bubbles do not appear in the bottle, it means that the milk is not flowing properly, and the cap should be slightly loosened for optimal performance.