Adcom XR-500 Extension Sensor Box...what is it?

I was given my system from a family friend and in one of the boxes is an "Adcom XR-500 Extension Sensor" Box. I cant seem to find any info on it. I believe that it is just an extension for your remote if you have your system in another room or behind a wooden stand or something. I also assume it is used for that because the wire attached is about 30 ft long.

Any more info would be great.
I actually found a link:

It is what I thought it was.

"ADCOM's XR-500II remote sensor with infrared repeater circuitry extends the remote control capabilities of your main ADCOM system to other rooms or locations. By aiming your ADCOM infrared remote at the XR-500II you can control your entire audio system from a remote listening area."