Compatible with Ember baby bottles, sold separately Level 2 bottle nipples deliver a medium-low flow rate that's suitable for babies aged three months and up Food-safe, BPA-free silicone construction ensures durability and parental peace of mind Top-rack dishwasher-safe bottle nipples are easy to clean Safe for sterilization in your sterilizer or in boiling water Flow rates are printed directly on the nipple for at-a-glance checking