Parsons & Parsons Co. Celluloid Collar Pamphlets, Probably 1926 or later

I recently purchased these pamphlets showing celluloid collars. They show the available collar brand varieties of the Parsons & Parsons Company’s three sub-brands in a given year. I have been hunting through Newspapers.com trying to work out the year of these pamphlets. I have tentatively described them as post 1926 since I own one of the collars, a Par Brand, Amherst collar which has a 1926 patent date on it.

Kant Krack Collars Pamphlet pg 1