This article is suitable for mounting an FD lens on an EOS EF mount. Used with a Lens2scope for using a telescope lens as rapprochement.Parfait After several attempts to use FD lenses with the camera turned me an error message. So I deleted the contact to avoid this error. In this case using the lens only .Make manual update fully open then select the diaphragm on the objective. the unit will announce the good illumination of exposure. satisfied with quality FD lenses. A report that there are non-contact rings and significantly cheaper. I realized too late for me because after you delete the contacts I find myself in this configuration.