Missing carb part .............

Today I took the carbs off my Z1000ST (US model) to discover a part was missing ...........
It looks like some kind of mini floatbowl is missing from the second carb, there are three treaded holes so there was something in the past. The bike is running good by the way.
What's missing, who has a partnumber etc.

Thanks,

Jur
Delfzijl
the Netherlands

That confused me too, but nothing is missing. That's where a vacuum sensor assy would have been installed, but the thing is kinda disabled on models after a certain year. Kawasaki didn't machine the orifices for it on your bike. The K&L accelerator pump kit includes the sensor diaphragm & spring, but the stuff isn't needed on some models.