THE CHIKUNO CUBE is a natural air purifier made from an ultra-fine powder of activated bamboo charcoal and clay minerals. The activated bamboo charcoal is a form of carbon that has been processed at a high temperature to make the cube extremely porous. Its micro-honeycomb structure helps amplify the surface area making this small cube able to absorb odors in an enclosed space up to 17 sq. ft. Use the cube in refrigerators, closets and bathrooms. Made in Kyoto, Japan, the Chikuno Cube won the Japanese Good Design award in 2008.