The present invention relates to the prevention of electro-chemical corrosion at charging pins, especially of a battery-powered handpiece and its charging station....http://www.google.fr/patents/US7733056?utm_source=gb-gplus-shareBrevet US7733056 - Prevention of electro-chemical corrosion at charging contacts of a battery-powered handpiece and its charger device
Prevention of electro-chemical corrosion at charging contacts of a battery ...
