5V 2.1A 3 USB Power Bank Battery Charger Module Circuit Board Step Up Boost [Black]

Description

All 3.7V-4.2V rechargeable lithium batteries, such as cell phone batteries, flat batteries, 18650 batteries, and so on. It could be connected to a lithium battery can also be connected in multiple sections of lithium batteries Lithium positive pole connected B + Lithium negative then B- 3 USB output, according to the device automatically recognizes the output 5V1A or 2A current on the phone. Flat charge, you can also charge three mobile phones at the same time.