It worked great on my Sony lens.

I bought the K&F magnetic CPL filter to mount on a Sony 18-105 lens. Although the filter is excellently made (even the magnet attaches well to the support ring), the main problem is that the lens cap (72mm diameter) does not attach to either the filter or the support ring, leaving the glasses unprotected. The return has begun.

Good ND Filter for the 18-135mm Sony E-Mount Lens

I bought this adapter to use Sony A-mount lenses from my Alpha 58 on the BlackMagic Cinema Micro. Am very happy with it. Nothing wobbles and there is no play. The wide-angle kit lens fits perfectly and the vignetting is not noticeable (logical! APS-C sensor of the Sony is larger than the 16 mm sensor of the BlackMagic). Lenses with a fixed focal length of 35 and 50 mm fit just as well. The only thing I haven't tried is the 50-200 zoom lens, but only because I don't plan on filming with it. Overall I am very satisfied and can recommend it. Of course, it has no electrical connection to the lens, so you can't use LANC to control the focus. But that should be obvious anyway given the low price. For such tasks you use active MFT lenses or a booster, but I haven't seen any speed boosters for A-mount yet.

The adapter fits the Sony mount very well, especially my Sony A7iv camera. I have tried a competing brand which I promptly returned as it blocked the frame but this one is immaculate, very well made with no defects.

The lens is among the best you can buy for Sony e-mount! This optic also performs very well in comparison to the much more expensive Zeiss lens. I bought it for the NEX-5. It was already very popular and often used. I'm now using it on the Alpha 6000 and I'm even more excited and satisfied because of the outstanding sharpness on the higher-resolution sensor. Sharpness = very good! Distortion = very low! Autofocus = very fast and very good (with hybrid autofocus of the a-6000) Anti-shake = very good and integrated! I have very often mounted this lens from the outset and make entire excursions exclusively with this lens. It simply has very good all-round properties! It's light, small and easy to take with you! The only small downside is the plastic sun visor, which is not that durable!

Analogue lenses have character and charm - that's for sure. And they are often many times cheaper than their digital counterparts. So why not adapt the good "old glasses" to a new camera? I already own the Neewer adapter for my Minolta glasses and now I wanted to test this K&F lens adapter for my M42 lenses on my Sony a7III and a6300. Today I also added the Minolta(AF)-NEX adapter to continue using my old Sony A-mount lenses.

I placed particular value on the following two points: quality and function.
1. Quality:
At this price (Minolta AF or Sony A-Mount), you can expect a little more from a lens adapter. To get straight to the point - my expectations were fully met.
Packaging:
The adapter arrived very well packaged and, in contrast to the Neewer adapter, even has a resealable plastic box. In this you can transport or stow it very well when you don't need it. Because we definitely don't want too much dust getting into the adapter and then into the camera.
Adapter:
The K&F adapter is made entirely of metal (brass and aluminum + a few steel screws). It feels very high quality and you have the feeling of holding something solid in your hand. The thread is very clean and well made. My lenses could be screwed in and unscrewed again without jamming. That's the way it has to be!
The fit on my Sony a7III with E-mount connection was very snug and tight. There was no wobbling or sliding after the adapter snapped onto the camera. It was also easy to dismantle thanks to the grooves on the surface of the adapter. This was thought through and not just valued for the optics.
The aperture selection on the Minolta AF adapter works excellently and feels "full" and easy to use. The f-stops therefore sit correctly and are not accidentally adjusted.
2nd function:
The adapter actually only adjusts the back focus of the "old lenses" to the new camera. He does this job excellently! Focusing to infinity works perfectly and the images are not affected by any additional lenses. Of course it depends on the lenses what the end result looks like - in my case I have the Porst wide angle 35mm f/3.5, the Auto Exaktar 135mm f/2.8 and for the Minolta AF the Samyang 16mm T2.2 used (see sample images).
I'm really happy with the K&F adapter and I'm sure I'll still have a lot of fun with it and my old lenses. I would buy it again anytime.

Edit 03/04/2019: I've even bought the Minolta(AF)-NEX adapter because I've only had good experiences with the products from K&F so far and I wasn't disappointed this time either. Great product and thanks to the choice of aperture I can now continue to use my old Sony A-mount lenses.

I bought and paid for the K&F adapter as usual via Amazon, but I get the money refunded as a product tester. As always, my opinion remains independent and honest.

John from Photoscrubs

This adapter is used to use an A-mount lens on E-mount cameras (in my case a Sony Alpha 6100).
The construction is good, it weighs just enough to notice that it is a quality product, it works perfectly.

You have to keep in mind that with the adapter you will have to use everything manually, that is, manual focus is obvious, but something I did not know is that the adapter comes with a ring to close or open the diaphragm but it does not show the step diaphragm (1.8, 2.8, 3.5, etc).
In the camera as you move the ring it will not appear which diaphragm is being used either, specifically in my camera it says F/0.0, even so, you can use the aperture priority mode and the camera calculates the shutter speed without problems.