it looks like a small u.p.s. (uninterruptable power supply).
the 9 pin d connector is usually a configuration/maintenance console port.
to be more specific, it takes a.c. in, keeps a trickle charge on a coupla batteries, and usually outputs line a.c., unless it detects the loss of the input. then it kicks in the battery backup, converting the d.c. out of the batteries to supply the a.c. outputs.
we use them on a lot of small computer systems at work.
The way that you wander is the way that you choose. The day that you tarry is the day that you lose.
Sunshine or thunder, a man will always wonder where the fair wind blows.