The product has a little vibrator that will break when it comes into contact with water. You are advised to clean the teether with a 'damp cloth'. I can't for the life of me see how this product made out of the design phase. It simply isn't practical to have a teether being rubbed with a damp clean cloth 10 times a day. If you are prepared to keep a sterile damp clean cloth on hand then get this product, I suggest anybody with a baby has a lot more to do than manage their clean damp cloth rota. Stupid idea, rubbish product. To top it off the product is mainly clear discs with no colour. Our little boy did not take to it at all.