Finally a way to use those wonderful old Canon and Tokina lenses and and and again. The adapter is solid and fits perfectly - not a cheap plastic part but a decent metal bayonet on both sides. The aperture is reliably locked so that manual adjustment can be made. The only drawback - there is no operating manual - but it is absolutely necessary. The description here on Amazon doesn't explain anything either - this led to me almost sending the adapter back because the camera - an EOS-M3 - no longer triggered. With another provider I found the important information that you have to select "Release without lens" under C.Fn III - Other - under 2 in the individual menu, otherwise the camera will block. After I had made this setting, there were no more problems - the camera can be operated perfectly. Focus and aperture are set manually in AV mode, the camera chooses the appropriate time - or, with ISO Auto, also adjusts the ISO setting. The great thing is that the old FD lenses are (still) available on ebay for cheap. Word hasn't really gotten around about what you can do with them - not even that they (eg Tokina) were and are excellent lenses. With this adapter they can be used again, and it is also inexpensive - therefore: clear purchase recommendation.