In 1973, I have buyed 2 PT109 EDSYN and I used them up to recently.
I only had to change the tip from time to time.
As they are now well worn and one of them has a broken spring, I recently buyed two new ones.
I don't know if it is EDSYN, HAKKO ou other who own the patent of this desoldering handtools, but at least EDSYN PT109 exist for a very long time ago. (well before 1973 !)