After the handpiece has held no longer flush cycle despite full charge, I decided for this variant of the overhaul. First of all: A little manual skill and experience is essential - otherwise you should leave it alone. The manual is very well executed and clearly. Read the instructions carefully - prepare tool / work - Replace battery - ready. The battery lasts for several days and again performed his duties properly. Since I had the handpiece now been opened, I also equal the deposits located on the shaft cover. This work was very well explained in the description. 5 stars because all expectations were met.
