The amount of air that is moving the device tremendously. At the highest level, the device is not very quiet, but at the lowest level possible to the device without that you feel disturbed, run long. In addition, I like the low power consumption, so you need not feel guilty when the fan is in operation for several hours. The stand can be only stressed by another, set up, adjust without joint. That's a bit of a shame. But overall this was a good value for fan money.
