This BPA-free 260ml bottle is ideal for infants with reflux and colic problems as a special airfree valve inside keeps the teat full of milk reducing air intake for easy feeding while the baby is sitting and effectively limiting colic and reflux. When feeding, make sure the airfree anti-reflux valve is pointing upwards in line with the baby's nose.When using powdered milk, make sure it is completely dissolved to avoid blocking the valve. Obviously, the bottle can also be used without the airfree valve. For hygienic reasons it is recommended to replace the teats after 3 months. The bottle and its parts can be sterilized in a steam sterilizer or in boiling water. For heating, only the container without the ring nut, the airfrre valve, the teat and the lid can be placed in the microwave.