Firstly, I have over 100 vintage lenses, so I've tried so many different adapters and this was the first K&F adapter that I bought in 2015 (I'm going through my old purchases to leave long-term reviews). Since then I've bought quite a few more K&F adapters for my other mount lenses, so at this point, you might be able to guess that I like these adapters a lot!So why do I like them so much? They are not the cheapest adapters out there, but for the price, they are the best adapters I've tried so far. They fit onto the camera quite snuggly which is obviously a good thing and the same can be said for the lens side on the adapter. Overall build quality is very good, even better than I would expect at this price point, so I highly recommend these to anyone using vitnage lenses on modern cameras!
03/01/2020
Excellent adapter, works brilliantly on my A7 with a 50mm Yashica. Have used this for a lot of paid work so continue to trust it completely. Robust.
04/06/2019
The adaptor itself seems to work fine. I've used it with lenses like the Helios 44M 58mm and Helios 28mm wide-angle with much success. However after shooting with it for several days, I've noticed maybe a dozen fine metal particles covering my A7ii's sensor. I can't be certain whether the particles came from a lens or the adaptor itself, but it might be a good idea to leave one of these adaptors on each M42 lens you have, or purchase a more expensive one that won't wear.
08/05/2019
Excellent adapter, does exactly as it should. I can now use my selection of M42 lenses on the Sony A7ii the way they should be used.
16/02/2019
09/12/2018
Good machining shame wasn't the one I needed a lot of forums misleading about the adapter I needed but will use soon when have the right lenses
08/12/2018
I waned this to test my old glass on a Sony FS5 camera and it worked perfectly.
21/11/2018