These conversion mounts replace the existing mount on your lens for use on Sony A mount bodies such as A900, A99 etc. The conversion is pretty straight forward as shown on the Leitax.com web-site. I have following mounts. All in excellent condition:
Leica R to Sony A:
Chipped for Tele-Elmar 80-200 F4 $50
Unchipped but special mount for Vario-Elmar 35-70 $35
Chipped for Lux R 80 $50
Unchipped 6 screw holes $35
Contax C/Y to Sony A:
Two Unchipped $35 each
Leica R to Sony A:
Chipped for Tele-Elmar 80-200 F4 $50
Unchipped but special mount for Vario-Elmar 35-70 $35
Chipped for Lux R 80 $50
Unchipped 6 screw holes $35
Contax C/Y to Sony A:
Two Unchipped $35 each