Equalises the pressure in the middle ear. Earpain / Freediving

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You blow up a balloon over the flat side, which your child inflates through their nose. This action opens up the Eustachian tube, allowing fluid to drain more easily from the middle ear. The balloon helps equalize pressure in the middle ear, relieving symptoms. This method also works for people who experience ear pain during plane flights or other pressure changes. Freedivers can improve their "mouthfill" technique by using this method.