Hi everybody. Carleton here. Long time listener, first time caller.
I'm looking for the model number and/or maybe info on where to get one. I know it looks similar to a TT chainwheel but I believe that this is track specific. In this pic it is attached to a DA crankset on a Cannondale track frame.
carleton - You're right, I think it's basically a 144bcd version of the Shimano TT rings. I've never seen one of these in person, but they're a common sight at World Cups / World Championship level meets. I'm presuming Shimano only produce these in small numbers for national teams maybe?
Other possibility is that they're rebadged Sugino ZEN rings, but they don't seem to have the same machining on them so probably not.