MAS VC210 In wall Impedance Matching Volume Control

Good afternoon,

I have a client who has a MAS-VC210 Impedance Matching Volume Control device and I don't know much about it but I need to interface to it. I can't find much information on the web. This is it here: http://www.federalstereo.com/masauma210wa.html


Is the MC-VC210 for line level inputs or for speaker level inputs? What is its impedance (as seen from the source driving it?) Is it powered? If so, what is the voltage? Is a user manual available?


Thanks,

Jason