Furling Main -- not In-mast.

[Ship's Cat 73]

I saw this yacht with and "out-of-mast" furling main in a 'harbour somewhere'.
I'm just curious ~ is this a "thing" that can actually be bought and installed on a yacht, or has that owner just rigged it on his/her own?
Just wondered if it's a foresail furling foil on a 'stay' between the masthead and the boom?

(Couldn't post the video so had to take a couple of screenshots.)

 

[Tranona]

Probably DIY although difficult to see in the photo how it furls. The angle of the outhaul line suggests it is not a mainsail shape as the clew seems too high

 

[vyv_cox]

I remember them being available commercially years ago but not for a long time now. An ancient thread on the subject In mast furling Mainsail - retrofit | YBW Forum In mast furling Mainsail - retrofit