In fact this was the first or one of the first frames disigned specifically for the Downhill. Designed by Marzocchi. Built by Verlicchi, an Italian company known for motorsport products. Verlicchi also built the S-Bike.
Frame sold through various brands.
Page from a Sintesi catalogue showing their ti/bronze Bromont:
A derived frame for Haro with the Haro typical concave top tube:
Verlicchi also contributed to the early Carraro FS frames:
It is clear the swing is Verlicchi. Don't know whether the front triangle is Verlicchi made, but the article is mentioning Oria as the tubing manufacturer. With this frame Carraro choose to connect the the seattube with the toptube through an additional tube. Normally, with the more familiar Verlicchis, there was an additional tube located between the seattube and the downtube. Another remarkable feature with this Carraro frame is that there is another shock fitted.
The Sintesi Hantrax reviewed below was made by Verlicchi too. It was issued several years later and it was more cross country orientated. It isn't as legendary as its downhill brother, but according to the testcrew it is a good bike. The review is not only on the bike as a whole, the red Marzocchi DH3s and the early Formula Discs are reviewed seperately too.