As some others I can only say that the build quality is just miserable. From 4 toothbrushes are just 2 years, three more or less defective. When one of the battery for not even holding a cleaning by, among others, the brush head wobbles extreme and does not vibrate properly. I once opened a brush, which is very difficult. The brush head holder is fixed with a screw that loosens itself, helps tighten, but not long. For the price, this is all extremely unpleasant and unacceptable. I can only advise: Stay away from this junk!