SoftShells Breast Shells were created with working mothers in mind. Offering the same care for sore, flat or inverted nipples as Medela's other shells, the SoftShells offer increased comfort and a more flattering appearance. Soft, silicone backs on the shells flex to match the contour of a woman's breast, creating a more snug, comfortable fit. The fronts of the shells are vented on the top to provide proper air circulation. Highly absorbent foam inserts protect against leaking.