One Size Fits Most - By covering the nipples and using pressure to suction inverted flat nipples, a form suitable for breastfeeding is created. WEARABLE EVERY TIME - The size is similar to that of the nipple. It does not affect the appearance after wearing when wearing a loose bra and other clothes. Packs In PP Case - A set (2 pairs) of pp boxes, with a storage box, easy to carry and store for your daily life and travel. When one pair is cleaned, you can use another one at the moment. HYGIENE AND HEALTH - Using soft medical silicone material which can be sterilized in microwave oven. It reduces the load on the skin and is comfortable to use. ADJUSTABLE - Flexible adjustment of the force of attraction by compression. Easily find the best fit for your strength."