The Beurer FW 20 foot warmer Cosy brings only at level 3 a sufficient warming effect. After 4 months the unit, however, was defective; no more heating power, the merchants sent a new device, but even this did not last longer than max. 6 Months. Complained again sent this another replacement device, but even this was after a few months the ghost. The brand Beurer I therefore can not recommend! While the dealers come to their obligation under the manufacturer's liability, but it is not worthwhile to claim the device again and again, waiting for the forwarding of returns brands to then return the unit back and wait for a new one soon anyway broken goes. I wonder, what about the quality control in the company going? Is there one? Anyway, I do not buy the next boot warmer at this manufacturer!