BambooMN Brand Granulated Bamboo Charcoal Odor Absorber in Decorative 6" X 6" X 1 3/4" Box, Green 4pc 4 pack of Passive Activated Carbon Air Filter/Air Fresheners, each in decorative 6" X 6" X 1 3/4" box Each attractive bamboo box contains approximately 200 grams of bamboo charcoal granules in a non-woven filter bag. Bamboo Granules come from a species if bamboo called Moso bamboo. Bamboo Charcoal helps improve indoor air quality by absorbing and trapping odors, allergens, and harmful VOCs. Re-usable for years, just place inner bags in bright sunlight for a couple hours twice a month to renew odor absorbing capability of the charcoal. The activated carbon in these air fresheners is derived from environmentally friendly bamboo.