Ahh, OK. The reason I ask is that I'm intrigued by these "reverse-tennon" style systems from the 30s and 40s, like the Pur-O-Matic mentioned above. The one in the 1942 Ad looks almost like a hybrid between patents 1888462 and 1936060. I have examples of both those patents and I see elements of both in that Ad. Just thought if yours had a patent number it would be a good cross-reference.