8 mini regulators, chained together, 0-30 psi, fully adjustable. I can only fit 7 kegs in my kegerator since I moved the co2 tanks to the outside, so each tank has its own fully adjustable regulator, with check valves, and shutoffs, the 8th is for my counter pressure filler. It allows me to adjust the filler to match whatever keg I am filling from.
This allows me, for instance, to keep my stouts at a low serving pressure, while I keep the wit beers at a higher pressure as indicated by style.

The collar is a new addition (this is the cause of my recent kegerator replacement), but as you can see, it allows me much more stacking room inside the kegerator than I previously had.
Nope, I'm not going to put taps through the collar, if I add any more, it will be an additional tower or 2 on top.