Quality construction with useful indicators. The fact that it takes an external power supply has its positives and negatives. For me as a professional, it is useful because with a power bank I can charge wherever I am without the need for 220 volts. On the other hand, even with a 9V 3amp charger that I have, it takes eight hours to charge two Npf970 batteries and this is called quick charge...! I wonder what it will do with a 5V charger... If you want normal charging speed, go elsewhere, otherwise arm yourself with patience because it will take a long time to charge and you will grow a beard.

It takes a long time to charge (for completely discharged batteries) more than the genuine one. However, it does not have something faster and of higher quality in a duo charger. It does not charge them simultaneously.
Correction: to operate in fast charge and charge 2 batteries simultaneously, it requires a 9volt/2ampere USB charger and not the 5v that most have

This charger is not pro initially. It is a weak charger that - for me - does not charge 2 batteries simultaneously. It is weak because it is powered by a USB cable and does not have its own powerful power supply. Possibly, if you use a powerful power supply with a USB port, it may save it somehow, but I used the most powerful one I had. It is definitely not a "fast charger". Also, the battery health assessment is not accurate, as it showed a damaged battery as "good" for me. I would return it.