The batteries both work, I have the little use, I do so little for the moment not attested to their durability, I would make a comment on this in a few months.
The charger has the particularity to integrate its transformer inside the holder, which makes it simple and use a moderate footprint.
In my case, the purchase was motivated not for the charger but only to increase the number of my spare batteries, so I do not expect much from the charger, and many of the batteries!
On paper batteries are of a higher capacity than other available suitable for GoPro Hero 4, remains to have if they really have the arguments in condition "use!
Anyway my opinion is moderate as I will not stop using the batteries and the charger for I do not consider it as successful.
Delivery: RAS
Packing: RAS