typical excellent sonicare product [SEP] i have been an engineer forever and an er nurse for years i know hype and bs at first glance and diplomacy has never been my long suit i have been using a sonicare toothbrush for many years it was initially recommended by my superb dentist dentist a man who chairs the dental program at a major nyc medical center i suffered from the beginnings of gum disease and a month after using a sonicare toothbrush it was gone when i briefly stopped using it it came back when i started using it again it went away again the engineering and construction of the sonicare products is impressive very few products of any sort are made this well this battery model which i plan to use while rving is another example of the companys superb products