I have installed this battery in an old ORAL-B toothbrush. I might be better to disassemble the toothbrush before buying these batteries. The original battery installation of this battery at least on my model was only 4/5 long and feasible only with a reduction of the housing base and thus quite fiddly. But the brush is running now but again without any problems.
As usual with Eneloop batteries are very powerful and hardly lose charge, the product deserves full 5 stars. The delivery time was slightly longer than usual from Amazon.