The description of all the operations is very good, because they are documented and thus for any layman to understand easily by large color photographs. There is little text to images, because they are comprehensible in itself, but in the right places, there is also always the right tip and the proper warning. So you need no special skill for the work, but what you need is a PC with printer, first to download and print out the instructions of the specified Internet address of the seller, because the does not lie with the battery; Second, a small soldering iron with accessories, thirdly, a little experience in soldering, and fourthly, a steady hand.
However, the works themselves are not in a matter of minutes, so almost done "on the fly" as it say here some reviewers. If you have never done this battery exchange, then take better an hour or a little more, because there are three little tricky steps: Right where you finally cut the solder tail of the new Plus-pole, "Thread" and must solder, and where the old negative pole off and is new to solder again. So do not let this time and you do not work sloppily, because the soldered joints have firmly and permanently remain so later in this vibrating toothbrush. Tell yourself that you have at least saved with the 1-1.5 hours 200 Euro. And for that the battery is a super bargain.