Of all the shower brushes like this one, you probably need this one. The battery is usually not charged all day. A good night's load from the dead is all you need. The engine is powerful, even if it is pushed, it does not weaken. After adding the extension, it flexes a bit when you apply pressure, but not to the limit. For stubborn stains you need a good cleaner. All brush heads fit well, as do all connectors. Everything is working well. I used it to clean my shower and the battery was notβ¦