It's an "ATZ fork"
It's one of the better fork I have used. It's working very sweet on small shocks because there's no bushings like telescopic fork, and the front part of the bike is quite stiff too.
The swiss man Philippe Perakis has won the kamikaze downhill with it and US boys were no happy that an european was quite 1s faster !!
Giovanna Bonnazi was world champion with it.
Francis Glatz, the creator thought that bumper didn't have to be use directly but with a lever.
I used this fork on a tandem for a long time !
Th bad side : quite heavy, and the fork is made of magnesium. Magnesium don't love water…
Well… it's really not acceptable…