Read battery safety link below
https://www.magicvaporshop.com/battery-and-charger-safety/
The Efest Slim K1 is a compact single-cell lithium ion smart battery charger. Efest Slim K1 Charger is a single slot charger with USB-C input and charges at 1A.

Click link for battery safety:
https://www.magicvaporshop.com/battery-and-charger-safety/

The Efest Slim K2 is a small, portable dual slotted charger, constructed to charge high-amp batteries in fast reasonable times.