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Amazon.com: Lasko FF305 Air Flex 2-in-1 20-inch Box Fan and Air Purifier in One with MERV10 Air Purifying Filter for Cleaner Air and a Cooling Breeze : Home & Kitchen
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How to make a box fan filter to clean indoor air of smoke | Interdisciplinary Center for Exposures, Diseases, Genomics and Environment
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Amazon.com: Lasko FF305 Air Flex 2-in-1 20-inch Box Fan and Air Purifier in One with MERV10 Air Purifying Filter for Cleaner Air and a Cooling Breeze : Home & Kitchen
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Amazon.com: Comfort Zone CZ200A 20" 3-Speed Box Fan with Carry Handle for Full-Force Air Circulation : Home & Kitchen
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