The Codd-neck marble lock in the neck of the bottle
Ramune is widely known for the distinctive design of its bottle, often called Codd-neck bottles after the inventor, Hiram Codd. They are made of glass and sealed with a marble; the codd head is held in place by the pressure of the carbonation in the drink. To open the bottle, a device to push the marble inward is provided. The marble is pushed inside the neck of the bottle where it rattles around while drinking. Therefore, the drinks are sometimes called "marble soda" outside of Japan.
People trying Ramune for the first time sometimes find it difficult to drink, as it takes practice to learn to stop the marble from blocking the flow. In one version of the bottle introduced in 2006, little slots were added to the cap where the marble was originally held. This prevented the flow from obstruction if the marble falls back into the cap. Ramune is also available in plastic PET bottles and cans.
Ramune is one of the modern symbols of summer in Japan and is widely consumed during warm festival days and nights. Empty bottles are usually collected for recycling at stalls where it is sold.