[Info-vax] DS10 disk bay question

[Hans Vlems]

Two weeks ago I was given a DS20E and a DS10.
The DS10 got VMS installed and after reading the quickspecs it turned
out there is a third bay inside to put a SCSI disk in (or an IDE disk
if one is so inclined).
In that bay is a metal part, a sheet of metal with two sides bent
upwards and fitted with one screw to the back of the cabinet. The
underside just lies on the disk bay and one side, the one with the
screw also blocks the airflow when fitted. Then again, if that was its
role in life a much smaller piece of metal would have done that job.
So: What is the purpose of this part?
Hans