stabilizer

Continuing with my research on the construction of the F4F I have noticed that the leading edge of the Horizontal stabiliser drops by just under 0.5 degrees. Effectively an Anhedral and not a dihedral as one would expect. The main spar is set back by 1 degree and is perpendicular to the vertical...

Trying to get an ID on this stabilizer and wanted to see if anyone can help ID. I can't seem to find an exact match. Anyone have an idea? The tag dates to pre-war (30's)