Nipple Pump set features a total of two Pump Sizes & four Ring Sizes. Perfect for nipple stimulation and pleasure, or to give you super erect and sexy nipples.Nipple pumps not only feel great, but guys also love them – because they encourage erect nipples. With two pump sizes to fit best and four ring sizes to make the grip perfect to keep those nipples erect and sensitive, your enhanced sensations will help intensify the eroticism of your play time.