[A/S] Vac Disc Brakes

["Jeff Golias" <jgolias@xxxxxxxxxxxxx>]

I've got a question for you late 70s owners.  I'm looking at buying a
'78 Sovereign Excella and I noticed on the badge on the side of the
trailer that it has Vac Disc Brakes.  Can anyone fill me in on these
and tell me if this is a good thing or not?  I noticed that there is a
hose on the front of the hitch.  Is that part of it?  Do I need to
install a special brake controller on my tow vehicle?  Any help would
be appreciated.

Thanks,