A20-QuickDock

Sound Devices A20-QuickDock for A20-Nexus and 8-Series Mixer-Recorders.

Dock your A20-Nexus to a Sound Devices 833, 888, or Scorpio mixer-recorder using the A20-QuickDock accessory, which provides convenient cable-free power, audio, and timecode connections.
The dock's quick-release mechanism allows the A20-Nexus to connect and disconnect from the 833, 888, or Scorpio with no tools, for easy remote mounting in seconds.

Go Cableless
When the A20-Nexus is Docked to an 8-Series:
Power must be provided by the 8-Series—A20-Nexus power inputs (TA4 and PoE+) are disabled.
The A20-Nexus and its NexLinked transmitters are controlled from the A20-Nexus front panel or its web app. The 8-Series user interface is not used for control.
Most A20-Nexus rear panel connectors are disabled apart from the antenna connectors, the USB-A port, and the Ethernet ports.
When docked to an 8-Series, the A20-Nexus Ethernet ports can only be used for control, not Dante.

Dock the A20-Nexus to an 8-Series and Use USB to:
Pair A20-Mini transmitters to the A20-Nexus by connecting a USB-C cable from the transmitter to the USB-A port. 
Attach a USB keyboard for entering text directly (e.g. receiver channel names) into the A20-Nexus.
Mount a USB thumb drive for updating A20-Nexus firmware.
Sync 8-Series timecode to an A20-Mini via the A20-Nexus.