Level up from medium to medium-fast nipple flow! Dr. Brown’s Level 3 Narrow Teat is the next step up in nipple flow for babies 6m+.Together with the anti-colic internal vent system, the Y Cut Narrow-Neck teat gives baby vacuum-free feeding that is clinically proven to reduce colic, decreases burping and wind, preserves nutrients, and aids in digestion for a good night’s sleep. While our bottle works best with the vent system, it’s great to have options when baby’s feeding develops. Just remove the vent and the feeding experience is similar to most teat-vented bottles.Made of super-soft, high-grade silicone, this teat is suitable for all Dr Brown’s Narrow Bottles.