Needs to be cut open with a small incision. - LED charging/discharging indicator. - Support Type-C USB charging and USB discharging. - Output: 4.2V / 1.5A. - Input: 5V / 1.5A. Input and Output.
The unit flashes red initially to indicate correct polarity, then briefly green to indicate charging required. During charging the led shows red and turns green when completed.
I had a small problem with the spring contact which needed stretching a bit. It now works well and takes about 2.5 hours to fully charge an 18650 battery.