Special feature: Waterproof Material: Silicone About this item: A simple cure for flat or inverted nipples--Through gentle suction, the pulls the nipple out into a small plastic thimble-like cup. In a matter of weeks of continued wear, the nipple will stay permanently erect. Non-surgical - uses gentle suction to stretch the lactiferous ductpainless,without surgery. Basically your nipples are not sore,Practice more,A noticeable improvement after a few days.Be patient. Easy to Use--Hold the Aspirator over the nipple with one hand and apply suction by pulling on the syringe with the other( A small smear of a non-petroleum based lubricant at the base of the aspirator may improve suction). A complete set--Nipple Corrector provide greater suction,you can use it at home,and Nipple Aspirator can easy concealing under the bra,you can use it during sleeping or working.Have a small handy carry case for storage to keep them clean, accessible and safe from losing for your daily use, also can be easily carried while traveling.