Took in 3- 5x7 lenses for CLA at my local (hour away) repair guy awhile back, he gave me a tote with 5 or 6 odd/old lenses, elements and shutters that I was digging around in today.
One lens is a B&L EF Anistigmat 3" f2; I believe it's a movie lens that someone has mounted it in a shutter.
Figured it might cover 4x5 so I dug around the Googles, found one, seems to be selling for 2000 Euros... any idea why? Is it all about the f2 or is this someone's wishful thinking?

https://arsenal-photo.com/Bausch-Lom...igh-Speed-Lens