This is a rip-off of a Kickstarter item (unless it was created somewhere else before that I don’t know about). The lower string is connected to a simple switch. When the string is in tension, the light is on. If you pull it by hand, the light comes on. The wooden balls have magnets in them to hold the string in tension to keep the light on. Beware, these are fascinating for children and cats!...
The wooden balls and string have been soaked in Chinesium, so are perfectly capable of conducting low voltage current. Simples really ;)
I don't think the string holding the balls would be conductive. It's probably just a wire contact pulled up by the magnetic force. If you were to just hold the top ball out the way and tug the bottom ball up yourself the light would likely still come on.
Probably wooden with a strong magnet in center,the balls probably just complete a 5 volt switch to allow the led light on ,I think the weakspot might be if the conducting wire to the two balls breaks over time,if the charger was included would be worth it
I like this