Sony S-Air wireless surround amp with wireless card. Model TA-SA100WR. This powers the rear speakers of the Sony S-Air system. It picks up the wireless signal from the base unit that would be wired to the TV or stereo. This unit is then wired to the rear speaker set. Its designed to keep wires from having to cross the room. This is only the amp unit your would still need remaining equipment. There is one for sale here on kijiji without this part. The manual is available online. The unit powers on and the green light flashes which means its not receiving the wireless signal it needs to operate. $50. Condition is good but I have never tested it.
https://www.sony.com/electronics/support/res/manuals/W001/W0012216M.pdf
