Khay đựng pin 18650

I salvage and repurpose batteries from cordless tools, power packs, and medical device batteries and needed a holder for all the batteries.  This holder will accommodate 100 18650 Li-Ion batteries is exactly the right  size to fit in a Prusament (or other brand) filament box. This saves tossing out a perfectly square good box.

I've also included holders for 26650 and 21700 sized Li-Ion batteries.