The Two-way Charging Hub for the DJI Mini 4 Pro supports USB PD fast-charging protocols, and can charge up to three batteries in sequence. You can also use it for battery storage or as a power bank (storing at least one battery with ample power) to charge your mobile device or remote controller via the USB-A port. The Two-way Charging Hub can be purchased as a separate accessory. It is also included in the Mini 4 Pro RC 2 Fly More Combo.