Green Ring is a device which is used to check air pollution.
Designers Park Jun Seok and Kwon Hye Rim have created the Green Ring, a conceptual device that can be installed in homes to check air pollution and filter it to some extent.
It is made from recycled materials, and is powered by pulling on the little branch on its side. Green Ring has different colored lights to indicate the level of air pollution.
[via Yanko Design]