Gardeners who want to reduce unpleasant odors in their indoor garden can attach a Mountain Air Carbon Filter to their exhaust fan to remove 99% of odor-causing organic particles in one pass. This eight-inch filter is effective to 810 cfm and maintains its odor-stopping power for 36 months. Unit measures 12” in diameter, 40” long, and weighs 60 lbs. Includes 8” flange.