From Manufacturer
Use the DJI Focus Pro Hand Unit to facilitate FIZ control of your manual lenses in tandem with your Focus Pro Motor and your RS 3/4 Pro gimbal stabilizer. Integrated 2.4 GHz technology can control the Focus Pro Motor from up to 524.9' away. Toggle AMF mode to engage autofocus, causing the focus knob to rotate simultaneously and allowing cinematographers to visually observe the focus status on the monitor and via tactile feedback. Manual mode can then be engaged and disengaged intuitively.
The A-B electronic marking points provide tactile feedback for endpoints and step-less damping adjustment, ensuring more accurate focusing. The unit also allows you to toggle the recording of your camera via Bluetooth. A 1.09" touchscreen display displays your current settings. Power is delivered to the hand unit via an NP-F550 battery.