Basically IFF, Mark.  It's listed as an Interrogator, connected to the ship's radar to light up and examine responses from aircraft in the area.

- Mike

On 8/1/2023 11:32 AM, Captain D. via MRCA wrote:
Anybody got any idea what this is and what it was used for:
 
Any help is appreciated. This came off  APA USS Gage before she was scrapped, and is now in the CIC onboard DE USS Slater.  We,re not sure it belongs there.  
 
Mark D.
WW2RDO