The NUK Nipple Protector helps let sore nipples heal and prevents rubbing against clothing. The anatomically-shaped, synthetic shells ensure an optimal fit and the special openings allow air onto the skin. The soft silicone cushion also feels pleasant against the skin. With the NUK Breast Milk Collection Shell, not a single drop of precious breast milk is lost as you breastfeed or express your milk. It is anatomically shaped, has a soft silicone cushion and a practical pouring device.