Hey Guys, Let me add my two cents worth to this discussion. I've used Tamron adaptall & adaptall 2 mounts in the Leica R4 mounts several times in the last 20 years and I can definitely tell you that there IS A GREAT DIFFERENCE in the mounts. Some will work with R4 & up to R7's BUT, not work on R3's???????? It appears that this has to do with the "cam" (arm/lug) spring pressure. I had one that would work on an R3 Safari that I had, but no way would it meter within 2~3 stops of where it should have been on an R4 & R5 at the time. I had to "Jury-rig" or "Art-ize" a separate set of springs so that I could interchange them, depending on the body that I planned to use! Talk about "A pain in the posterior"! I still have the Tamron lenses, since they were unusual and wonderfully performing lenses, but I now only use them on my Nikons, Pentax LX, and a Rollieflex SL35E (Now there's a "moldy oldie" with some serious quirks!! Just some observations, Art Tafil natstek@xxxxxxx ------ Unsubscribe or change to/from Digest Mode at: http://www3.telus.net/~telyt/lrflex.htm Archives are at: www.freelists.org/archives/leicareflex/