The Twistshake Black Glass Baby Bottle is made of borosilicate glass, which is a very strong and lightweight material. The ergonomic design of the bottle makes it easy to grip, it is covered with a protective film of biphenol A-free silicone that can be removed and protects the hands of the little ones against heat. This bottle is ideal for nursing babies, since the shape of the nipple is reminiscent of the mother's breast and works preventively against colic that affects many nursing babies, thanks to its anti-colic valve that prevents air inhalation leftover reaches your baby's delicate stomach. Naturally, it is possible to replace the teat with other of our pacifiers so that the child grows with the use of the bottle. This bottle is naturally odorless and contains no harmful chemicals such as Phenol A, PVC or Phthalates. The silicone in the bottle is labeled with the type ML and US FL. The bottle can be heated in the microwave and has the ability to go from freezer to boiling water thanks to its resistance against heat. Thanks to being made of borisilicate glass, the bottle is scratch resistant. The glass container of the bottle can be washed in the top section of the dishwasher, but we recommend that you wash the other components of the bottle by hand, as they may discolor when washed in the dishwasher. Characteristics: Heat resistant borosilicate glass. Medical grade silicone teat: size M (2+m). Anti-colic – Twistshakes anti-colic function valve prevents colic with a free flow of food. Extra wide container neck - easy to fill and wash. Lavatory. Light weight. Ergonomic design with protective silicone coating that can be removed - easy grip for baby and adults. Quality grade ML and US FL. Biphenol A free – safe for you and your baby.