The used DJI Ronin 2 SDI Out Cable carries an SDI camera signal from the Ronin 2 to a monitor. It connects to the SDI output port on the gimbal and SDI input of the monitor.
The cable is 19.7" in length and is a replacement for the one that comes included with the gimbal. The camera signal is separately sent to the gimbal via an SDI In Cable, sold separately.