Used on a Sony Alpha 7III (FE mount), this ND filter is superb. The finishes are very good, the notched indicators on the ring allow you to calculate the number of stops.
I mainly use it for videos, I didn't notice any “cross” effect even at max.
It's confirmed!

I bought the filter for my Sony Alpha 7 iv. The filter comes with a lot of accessories. Everything is included, from cleaning cloths to a lens cap and a shockproof protective case. The ring for adjusting it is easy to move but at the same time not so easy to adjust that it adjusts itself. Everything seems very solid in terms of quality and the filter itself does not cause any reflections, as is the case with some other filters. Of course there are better filters, but for the price this one is unbeatable. Perfect for amateur photographers and videographers.

The filter works very well on my Sony Alpha 7 III with a Tamron 24mm F / 2.8. There is no cross formation or other unsightly effects. The workmanship feels good and comes in a practical plastic case. As always, the shipping was great with Amazon. I can definitely recommend the 67mm version of the filter. BUT, the filter may not take into account that well in other sizes.

Fits my pentax k lenses and my alpha 7 ii camera

I bought the Canon FD Adapter for my Sony Alpha and am very happy with it. For the aperture, it is important to set the adapter to 'Lock' when adjusting, otherwise changes to the aperture will have no effect. Has replaced my previous adapter because the quality is much better. The processing is 1A, no fluctuations or the like and I don't see any stray light even with longer night shots.

I got this tripod for my Sony Alpha 6400 camera, and it's great so far. I was looking for something to my Alpha 6400 which will serve the purpose of both tripod and selfie stick. The easy detachable monopod feature is great for taking some great selfies with its multi-angle rotating ball head but it is little bit heavy when used as selfie stick. It is also pretty light to carry around, easy to configure, and pretty stable for carrying to my hiking tours and is good fit in my backpack.

Excellent filter lenc for my camera. I took some pics with this on my sony 6000 alpha camera, and really loved those.

I bought the K&F Concept ND filter for my Sony Alpha 7 III. I use the 67mm version.
The filter arrived the third day. Everything was well packed and undamaged.

The processing is really impressive. Very clean glass and no scratches or anything like that.
The intensity of the ND filter can be continuously adjusted from ND2 to ND400.
I took a few test photos with the filter and am absolutely satisfied.
The only drawback for which there is a star deduction: At the maximum filter level you have a bluish shimmering X in the photo. This is a bit annoying, but if you turn the intensity down to just below the MAX level, it disappears again.

All in all, you can't go wrong with the ND filter from K&F Concept. At a reasonable price you get a universal ND filter. I give it a clear buy recommendation and because of one shortcoming 4 stars.
I hope I could help :-)