Nighttime Freeflow Pacifiers Ideal for baby's delicate skin, these pacifiers have a curved shield with extra vents to promote air circulation. This helps to prevent skin irritation and chapping. Designed with the highest safety standards, AVENT pacifiers have odorless, tasteless silicone nipples that reduce risks related to allergies. As recommended by pediatricians, the nipple is symmetrical, so right side up or upside down, AVENT pacifiers ensure the proper development of baby's teeth and gums.