Essentially, FITASC is European sporting clays, only don't assume that it is physically the same as your Yankee concept of sporting clays.
Rather than using the machine for just one stand, after which the shooters move on to another test, FITASC shooting utilizes a number of different stands around a given trap setup.
It is entirely legal to throw only ground-hugging rabbit clays; some European FITASC courses, I am told, do indeed use several rabbit traps to run targets uphill and down and in criss-cross routes rather than to have a flying target involved.
This, FITASC is a form of sporting clays that is shot when there is less land available.
Besides using less land, one nice thing about FITASC is that it gets shooters through the course quicker.
Another difference between sporting clays and FITASC is that the latter allows two shots at each single target, and it is scored a hit whether it is broken on the first or second shot.
Germany's Krieghoff is well known in clay circles, but recently they have added a side-by-side and a lighter over/under called the Parcours that is intended for FITASC
competition, but there's little reason you couldn't pop some cloves here or in Argentina with it.