The flange measures 2" like all other 1.5"TC ferrules. The ID is 35.1mm just like standard 1.5" weld ferrules.
The front of the flange does not have flats for a wrench. The easiest way to hold the flange for tightening is to clamp any other TC parts on with the gasket and clamp. Once tight, you can insert a long rod or screw driver into the hole of the wingnut.
