Dyson Tower Fan & Air Purifier on sale! A seriously cool double-duty device, the Dyson TP01 Pure Cool combines the function of a tower fan with an air purifier to produce a powerful stream of smooth air. Its Intelligent Purification system monitors your air and reacts precisely with a 360-degree glass HEPA filter that captures up to 99.97% of particles as small as 0.3 microns. From Dyson.