I understand not why because a jacket is necessary - at the Oral B versions for adults is because ultimately no. And where is more to it can go even more broken. The brush is perfect for toddlers and go a different way with things around as mom and dad.
Anyway, this shell is broken off after a short time. One can now argue whether the error in the child is, or to the parents who have not been paying attention, or at the senseless shell. I say it this way ... I see the guilt rather with the brush. A third time I will not buy.