Low Budget 2X18650 Batteries 3 D Box Mod with JiGuan-1600T 160W TC Chip

you need : the chip:
https://www.fasttech.com/p/3763901

the 510 er connector:
https://www.fasttech.com/products/0/10011689/3441300-510-connector-for-e-cigarette

and finished is the 30 dollar boxmod ....