This is 18650 battery cap and holder for 6s setup. I also included a remixed version of the 4s holder here too.
I Remixed the 4s 18650 holder from:
Warning!!!!! 18650 flight packs are not for everyone.
What is your purpose with these batteries? If you want to go fast and race, these batteries is not for you. But if you are able to manage your amp draw and fly for maximum flight time, then when the correct 18650 cell you can achieve longer flight times.
Update (Mar 05, 2021) I just remixed this holder to fit a larger 21700 size Lithium Ion cell. You can find it here:
Printer: Sovol SV01
Filament brand: SUNLU
Filament material: SPLA
Notes: I used SPLA because it a mix between PLA and PETG.