Please refer to the video for instructions: https://youtu.be/cCXR3Z-wcoc

Parts List:

2x18650 Battery https://s.click.aliexpress.com/e/_DDVqhdL
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1xDC 3~35v Step Up Module LTC1871 (MAX 6A) https://s.click.aliexpress.com/e/_DefuOVR
1xPotentiometer (B50K) https://s.click.aliexpress.com/e/_DBxit7n
1xBanana Plug to Alligator Clip Connector(1m) https://s.click.aliexpress.com/e/_DlxOpgt
2xBanana Socket (4mm) https://s.click.aliexpress.com/e/_Dm4wVbr
1x18650 Battery Shield(V8) https://s.click.aliexpress.com/e/_Dm5WSP7
1xPositions Connector Terminal(Small Type) https://s.click.aliexpress.com/e/_DCix2lr
1xFuse Holders (5x20mm) https://s.click.aliexpress.com/e/_DmsqbWl
1xFuse Sets (5x20mm) https://s.click.aliexpress.com/e/_DE7cqav
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Heat Shrink Tubing https://s.click.aliexpress.com/e/_Ddri5N3
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M3 Bolt & Nut Set https://s.click.aliexpress.com/e/_DCg2Sr3

In the meantime:
Happy making!
Please post your makes builds.