Knox 5.5" x 2 3/4"
I got this beater some time ago from ebay, as a project hat. It will get a thorough cleaning, then stretching and brim-cutting down to 2 3/8", thereby removing the two heavy moth bites.
The felt seems to be of mediocre quality. The brim is fairly soft; the crown, however, is a little stiffer as if a previous owner had worn it in a downpour and then steamed the hell out of it, activating the stiffener as much as possible.
The brim treatment is what has been referred to as a poor man's cav edge (see pics): it's an underwelt which is not sewn through, with the tension of the stitching row imitating a cav edge (on the top side).
The liner is a nice silky fabric without any protecting layer or remnants thereof.
The reeded sweatband is 2" wide.
I wonder if someone might have a date guess? My guess is early 40s.