Lansinoh understands that sometimes mom and baby need to be apart - that's why we designed the NaturalWave Nipple to help baby use natural sucking motions and maintain established breastfeeding patterns. Easily switch from breast to bottle & back again. 1. Nipple tip: Baby controls milk flow. 2. Inner vertical ridges: Makes it stronger and collapse-resistant. 3. Extra-soft flexible silicone: Adapts to baby's palette and encourages natural tongue movement. 4. AVS Anti-colic Air Ventilation Systems: Reduces intake of air. 5. Wide, textured base: For easy latch on and secure seal. Clinically proven to reduce nipple confusion. Soft flexible nipple enables baby's natural sucking motions. Easy to clean and assemble. BPA BPS FREE. Dishwasher and microwave safe. Recyclable packaging.