Circut board in a little 3s Zippy pack

[Bondonutz]

I received a few packs from Hobby King/City and was getting ready to change the 3s packs to a heavier gauge Lead wire and discovered under the heat shrink a "circut board". Sorry if I live under a "Lipo Rock" but I never seen this befor or read about this. I'm sure they used a board to make in easier in some way or to add Efficiency.
It just made me go "Hmmm,thats interesting" and thought I'd share.
If this is old news then I apologize.


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