Made for the XT8, outer diameter measures 9 1/2" and has some adhesive pads to take the diameter down a little, if you want to try it on another scope. Filter has a couple light marks on it which were there when I bought it new. Orion's literature states that "pinholes and scratches are common in all glass solar filters. Microscopic particles can not be completely elimianted in the coating process." I've never seen any diminishing in quality from this.
$90 shipped CONUS($129.95 new)