... 315mm, length:300-1250mm 3.Carbon layer thick: 35mm,50mm Activated Charcoal Air Purifier, Air Filter for HVAC systemsHcsino*Carbon layer thickness ... sponges and trap most airborne gases and odors. Activated carbon is charcoal that has been treated with oxygen to open millions ... , Heavy duty hanger, Flexible duct... Rope Ratchet Filter Hanger Activated Charcoal Air Purifier, Air Filter for HVAC systems