Hello. I'm looking for some help from the knowledgeable gentlemen of Leica Forum. I have what I believe is a Focomount. It has an internal thread for M39, is adjustable for focus, and currently holds a Carl Meyer 50 APO-X-f:9 lens via another adapter (m39-> 25mm). I believe that this makes it a focomount #3 ZQGOO 16688. Is this correct, and does anyone know anything about the Carl Meyer lens? I can't find anything about it on the net.