Hi Jerry-
Sorry, my friend owns that tab and he is in another state-all I have is the 2 scans I posted, which he sent me. With that plain cardboard backing or whatever it's made of, I couldn't help but notice that the folded around rear overlaps are not neatly symmetrical, as is usually seen on the reverse side of normal tabs, with evenly-sized overlaps wrapped around buckram.
The tab illustrated also has runes spaced unusually far apart...makes me wonder if it started out as something other than a collar tab?