As a replacement battery for my Braun Oral B toothbrush the perfect replacement. Affordable and suitable. I have not seen to pay the overpriced prices just because of the mention for Braun Oral B. Youtube has some videos in which the conversion is accurately described. Just disassemble the toothbrush was not easy because of the seals, above all, the upper blue sealing ring at the head of the toothbrush was to accomplish difficult and with great effort, but after about half an hour I had the battery by means of soldering and desoldering changed. One should have to deal with it, the solder tails of the batteries need to be adjusted, be bent and soldered to the old solder tails. Now, after 2 weeks I can say that the reconstruction has fully paid off. The toothbrush is as on the first day and the battery charge is sufficient for a long time. Topp!