Burleigh Brooks introduced a legend with little fanfare in the 1970's with the f9 Computar series.
There is a lot of information about these lenses here. They are somewhat rare. Kerry Thalmann sold one here, recently.
This one is in perfect shape. Shutter runs crisp and nice like new. After Burleigh Brooks folded, these were offered by the Kyvyx Corp. and re-named Kyvytar. Someone noticed that when they are in a shutter, you can get an honest f6.8 out of them fully opened, and they were marketed that way. They also marketed the convertible aspect which was highly popular in that time period. So it's 240 with both cells and 422 with rear alone. Both scales are on the shutter. I never looked through it converted. I'll bet it's pretty nice though.
I've had it on the 11X14 and it covers with modest movements possible. I also have the 270 f9 so this is sort of duplicated by that one which I WILL keep.
$995 shipped in USA. More to other lands across the sea.