I have several devices that run on rechargeable 3.7volt lithium-ion batteries which can be recharged whilst in the devices. This means I can't use the devices whilst they are charging which can be a pain. To avoid this waiting I decided to buy some spare batteries but I also needed to buy a charger and thought this one was within my budget and was what I needed.
This charger came in a box with a user manual and a USB to micro USB cable. The charger will hold two batteries of varying length thanks to the connector which is on a spring and can move up and down. The charger uses power from a mains powered USB plug, phone charger, USB port on a laptop or games console etc. I use my power bank to power the charger because it is more convenient for me and I'm happy with the way it works and has solved my problem.
To see this Dlyfull USB 3.7V Li-ion Intelligent Battery Charger on Amazon use the link below: