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If the battery in this little gadget runs out, I still have to contact someone over there to buy a new one. The battery inside is particularly expensive, and they keep tight control on it; every time I need to buy one, I have to contact a specific person, otherwise, I won't be able to purchase it.
Because every part of this gadget is so valuable, he always took good care of it, even bringing it with him when he traveled far.
He had secretly sought out experts to study it, but they couldn't figure out how it worked. If he wanted to continue the research, he would have to spend a lot of money, and there was no guarantee they would achieve any results.
In the end, he had no choice but to give up.
Uncle Bao wondered: Could this be "legitimate" technological secrecy?
Feng Yi listened as Uncle Bao recounted his experiences of asking their grandmother for the tool, as well as the several occasions of buying batteries.