... carbon carving crafts frame series product have developed hole structure, the major is alveolus, from outside to inside Product structure: Active carbon ... which be branched by the filtration hole. Active carbon series product can adsorb various of venomous gas ... (formaldehyde, benzene, dimethylbenzene, ammonia, chlorine, carbon monoxide, sulfur dioxide, smog, peculiar smelling, etc) from ...