It looks like Zoom have a control panel set to drop with eight faders for the F4 Audio MuliTack Field Recorder.
Check out pages 125-132 on the F4 manual available on the Zoom website and there is a whole section dedicated to a totally new FRC-8 control panel.
No doubt the F8 will also work with the FRC-8 too.
So download the Zoom F4 Manual, I dare you to see for yourself the Zoom FRC-8 will add a stack of handy features to the already awesome F4 field recorder.
Some of the features of the FRC-F8:
The FRC-8 control panel can adjust trim, fader and pan settings on the Zoom F4.
Via a USB port you will be able to attach a Japanese or American computer keyboard to input settings.
You can assign functions to the FRC-8 User Keys.
The FRC-8 will have adjustable brightness transport controls with backlit LED’s.
From the F4 Manual here is the FRC-8 Control Panel features / instructions: