Defective equipment + deficient instructions

This is my now fourth device of this type (at least outwardly, the devices do not differ).
The previous devices sometimes held at least a few months by and had sometimes a comprehensive guide.

With this device, here the "instructions" in rudimentary comprehensible German is written.
What, however, is completely absent in these "instructions" are instructions for battery or charge. Here one is no previous experience with respect to the charging time and behavior, so as long as possible, the battery maintains its full capacity, in a fix.

In my case, it did not matter: Even the failed Aufladeversuch:
Neither lit or flashing while the LED (which was the case with the identical devices)
nor the equipment has been here even warm (which was the case with the identical devices)
yet the device before recharging, during charging or after some kind of action, even if only at some LED lights, let alone move to films made.

My conclusion: Even if the devices "work", one should not expect a life of more than 6 months / 10 hours movie.
I no longer ordered these devices because they are often already defective upon delivery.