When connected to electricity:
Switch Pro Controller Charging Status The front light will indicate green when it is charging.
If it is fully charged, it will be off.
Switch Joy-Con Charging Status When Joy-Con Controller stays in snugly, the red lights come on and start charging.
When Joy-Con is fully charged, it turns green.
Voltage Output: 2A=4 x 500mA (nintendo switch joy-con), 5V=2 x 500mA (pro controller)
Fast-Charging Simultaneously charge Switch Joy-Con Controllers and Pro Controllers at full speed. You can just plug USB cable into the switch dock or any 2A USB power brick.