In all fairness, Duplex is kind of an odd term for a master ring cylinder like this, especially considering Yale sold a lock called the "Duplex" that was a two keyhole, bicentric lever lock.
I'll look that up.
thank you. wylk is awsome.
Just found Patent Number #1069734 as saying Duplex Cylinder....Timothy....
I have sent a private message with suggestions.
Thanks for info received. I also thought all clock keys had square drive. Some Banjo Head nuts are Hex Shape. Anyone have any thoughts on this? - Rex
Just look it up as it call Flat Spring Steel Asst....Timothy....