One size fits all ages, from newborn to weaning! Multi-fit wide-mouth type, heat-resistant glass All parts are made in Japan, and the heat-resistant glass bottle is durable and resistant to stains. This bottle comes with a multi-fit nipple made of silicone rubber that encourages the baby's sucking behavior by allowing milk to seep out and controls the flow of milk according to the baby's sucking strength. Sterilization by boiling, chemical solution, and microwave is possible. *Quoted from ChuChu official Used only a few times #chuchu #chuchubaby #babybottle