Fortitude 100% Natural Auto Air Purifying Bamboo Charcoal Bag/ Air Freshener Formaldehyde of indoor decorate a legacyTVOC,, ammonia, hydrogen sulfide, etc Harmful gas has good adsorption and decomposition. Improve the bedroom environment Bamboo charcoal with humidity two-way regulating function, Wet to open air conditioning room can be automatically, maintain moisture balance Bamboo charcoal can increase the amount of negative ions in the air, Create a good physical and mental health work, living environment. It is good for your healthy to put charcoal in your car and your home Set of 4(100g*4)