Electronics knowledge test! What is the secret component? NO! Is not a battery!

I can bet no one can solve this test :))))))))))))))))) The right answer it will be reveal in one week. Note: The switching power supply board from the video is based on LM2596
working on voltage range 4.5V to 40V
First clue: https://youtu.be/zhfKgdVWtCI
The gimmick: https://youtu.be/u5GcKiA7_LY
The answer: https://youtu.be/467YBZYGxYM
WebSite: https://sorinelectronics.co.uk/
USB power meter: https://amzn.to/3CRjsbZ
Thermal camera: https://amzn.to/3ECIqfY
ST-862D Hot Air: https://amzn.to/3eqDOQ2
Electric Screwdriver: https://amzn.to/3cgMAfy
Rosin colophony: https://amzn.to/3X97Vwi
CPB Heating Pad https://amzn.to/3Fm4IUa
Low melt solder: https://amzn.to/3T6mHBD
Wick wire: https://amzn.to/3CHWYdc
Tweezers: https://amzn.to/3SKTA7h
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