It’s [Steve’s] LED light ring for a stereo microscope ... We’ve already seen his custom stand and camera add-on. This is no exception. The device uses a fab-house PCB which he designed.

DIGITEK® (DRL-12C) 12 Inch LED Ring Light with Stand 5ft & Smartphone Holder - USB Powered, Color Switch Mode, Adjustable Brightness & Temperature Controls - Photo, Video Shoots & Live Streaming ...