Polygon lathe cutter mechanism - video

Polygon lathe cutter mechanism. By Make it Extreme. 24:15 video:

https://www.youtube.com/watch?v=oCFfvmREacA

Is this a recreation or adaptation of an existing lathe add-on mechanism or is it a wholly new device?

It seems (to me, at least) pretty well designed to retain perfect concentricity of the shaft or part you're adding the polygonal feature to; reducing the setup time and possible error required to move it to the mill to machine the flats, and quicker than setting up a separate spindle on the toolpost to mill them woth some sort of dividing fixture on the headstock.

An excellent build, There have been many times I wished I had an attachment like that for my lathes, with at least 1 exception the Timken bearings in the spindle mount will trash out in short order being exposed as they are without a seal to keep chips and dust out of them.
While I like and often do use Timken bearings for many things I prefer whenever possible to add and additional angular contact ball bearing either sealed one side or at the very least shielded on the business end of a spindle with a provision to inject lube into the spindle housing.