Carrier AOP

[mudeng]

Can anyone help to identify the purpose of the fitting seen outlined in red on the enclosed. It appears to be a bar, threaded at one end, with wing nut fitted and a claw attachment above, or part of it.
The same thing is shown on the stowage diagram for the MkIII.

I am also looking for details of the cable reel holder that held the telephone cable reel at the rear of the vehicle.
I have an overhead shot, but I need to see the shape of the holder itself, was it a cast item or metal brackets?

Thanks in advance if you can help.

George Moore.