Do yourself a favor and buy the Sonicare FlexCare. The newer FlexCare models are an upgrade without the screw-on design flaw of this Sonicare model. This model has a hideous design where the saliva and other brushing liquids seep down into the inner mechanisms of the hand piece and pool up in a really disgusting way and requires you to take it apart and clean off inner crevices made up of metal and plastic parts. The new design eliminates all that slew of slime. This brushing action is fantastic, just like the new one, but this design stinks...literally.