Slightly awkward to connect and lacks a thread for filters. Otherwise, works fine. I bought this when the Edge HD 9.25" was new, so maybe they have filter threads on them now?
This reducer does work on the 9.25" EdgeHD but it falls far short of covering the full APS-C field on my camera (stars beyond a central 16mm circle on the sensor are comet-shaped). I'm using Optec's own spacers and adapters with the reducer so it appears that there is nothing I can do to make the image quality better on the corners and far sides of my camera's sensor.
One of the best investments for my 9.25 hd - have no regrets shortened my exposer times by 1/3 & maintaining the edge hd focal plane . Be sure to get the proper camera attachment for your needs ! Came well boxed , excellent condition & well made !