The file 'DIY Power Bank 2x 18650 Cell 3D Printer Model' is (stl) file type, size is 301.7KB.
Power Bank case for 2x 18650 cells. How to build one, click link below:
http://feriar-lab.pl/jak-zrobic-powerbank-ze-starej-baterii-z-laptopa/
2 versions of case: