Specially designed for use with VentAire® Bubble-Free System only (sold separately), this 2-pack of Stage 1 VentAire® Silicone Nipples from Playtex® offers unique, non-vented, medical-grade silicone nipples with a dripless feeding slit to prevent leakage. Designed for newborns up to 3 months, the distinctive light-blue tint reminds mom which bottle the nipple goes with.