Interesting extinguisher, Rich, although that's the first of that type I have seen so have zero data on it.
Some of us a passive BlazeCut suppressor system, somewhere from one meter long to about 2 meters and circle the engine bay with it.
http://blazecut.com/small-enclosures/description/
Others use a bottle-type with extinguisher nozzles pointed at the carbs and engine. Danny P has a bottle type on his Spyder similar to this:
http://blazecut.com/local-application/description/
I think Summit Racing and Speedway Motors sells complete systems, too.