Used 25SS style gear case, empty, that has a deep skeg.  We had three of these and they all looked the same.  They appear to be based upon a 25SS gear case but with a deep skeg. Hard to see evidence without stripping the paint that the deep skeg was welded on a 25SS gear case.  It is not shapped like a standard 30H or 20H deep skeg as the lower corners are not rounded off and the skeg is a little thinner.  If these were not done by the factory they were done by a person with a lot of skill.  These are meant to have the metric drive shaft used in either the 25SS or 20H style.  These would not be legal in APBA stock outboard classes nor with the 20H mod but with a 25SS mod engine.