Made in France, this dates back to the early 30's.
There are two versions, a 7tooth and a 13tooth. The 7tooth is supposed to be the more aggressive of the two but I've found the opposite. The 13tooth gives me a BBS with two passes.
If I look at the patent drawings, it looks like the 13tooth is the earlier patent. From the drawing of the 7tooth head it would appear that it was to be use the opposite way with the cage opening at the bottom, but then it's no longer adjustable.
Adjusting it: When you tighten the handle it flexes the cage and thus adjusts the gap and the angle, but it also tends to bow so I am not really convinced on the effectiveness of it as an adjustable. Repeatability of a setting is also difficult as there is no scale.