You might be asking which external batteries work with Solo PRO, and can you use any USB-C output battery with the unit?
Any USB-C Power Device capable of outputting:
Can be used.
Does the Solo PRO Support Fast Charging?
No, the Solo PRO uses a steady power charge similar to laptops, unlike some phone handsets that now support pulse charging or fast charging. While powered off, the Solo PRO takes approximately 2 hours to reach a full charge from completely discharged.