I purchased this charger for it A/C & D/C power sources and two (2) battery charging as I am going to Yellowstone this next February and the cold weather will eat up my batteries. This unit will allow me to charge my batteries in my car while on the road or hotel. When I got this charger, the D/C power worked fine, but I could not get the A/C to work. Long story short, the A/C cord was only delivering 2.6 volts. Amazon sent me a new one as soon as I asked to return the deflective unit. I was not able to get it in time for a four (4) day shoot but it was waiting for me when I returned and everything works fine on this new unit. My first charging of a battery that was down to 50% seem to charge faster then the factory charger that came with my Canon 5D mark II. I am sorry that I did not time this, but maybe sometime in the future. All and all, I am pleased with this unit and look forward to using it on the road in cold weather.