Quick carb question

[Caper]

I just picked up a CV 27414-99B to put on my Heritage, have a Mik on it now but wanted to go back to the CV, mostly for the ease of tuning them.
There is a fitting on this one on the same side as the fuel inlet at the back and the port for it is in by the butterfly...my question is ....what's it for?? I don't remember it being on my '90 carb.

 

[glider]

Probably for a VOES petcock. (vacuum port)

 

[Caper]

Yeah, must be, I thought they just ran a T fitting to the vacuum petcock from the VOES line. Another one of the minor changes...thanks glider