mr white or anybody else, what kind of adapter is is on the disc on this bike?

http://www.fixedgeargallery.com/2006...ndyWhite_2.htm


I need some kind of freewheel to track adapter for my disc, I know that HED makes one but it lacks lockring threads (this will only be used on the track so i don't know if it makes a differnce, does it?) I know a guy at work has one that has set screws and is theaded for a lockring and he says it works great. I am looking for more options, any suggestions?