Blueair Pure 211+ Air Purifier If you're thinking of investing in an air purifier, then try the bestselling Blueair Pure 211+ Air Purifier ($300). It has two filters and this model can clean air in up to a 600 square foot room. Image Source: bedbathandbeyond.com Blueair Pure 211+ Air Purifier $300 from bedbathandbeyond.com Buy Now