The K&F Concept Nano-X True Color Variable ND Filter Neutral Density Filter ND2-32 is relatively weak because other filters go up to ND1000. But of course, it has a fine gradation at the bottom. I tested it on running water and that in strong sunshine. This was then only possible manually at aperture 8-11 and a slower shutter speed. But I also have to admit that I'm not the professional and I don't know all the tricks. In addition, there is hardly any flowing water in my area that can be allowed to flow smoothly with such a filter. I live in the lowlands. This filter has 1-5 stops. From the same manufacturer, there is also a filter with 1.5-10 f-stops, which is even slightly cheaper. That would be the K&F Concept Nano X-series Variable ND Filter ND3-ND1000 gray filter. I would rather use it for strong sunshine. This one is quite okay for German bad weather, i.e. when it is cloudy.

The ND2-32 neutral density filter comes in a very practical leather case. There is a ribbon on the side, which helps to eject the filter. The clasp is magnetic. The adjustment of the filter is smooth and simple. I use a Canon EOS M10 with a UV filter. This filter could be easily attached to it. Only the cover cap (lens cap) then no longer fits on.

Conclusion: The quality seems very good to me and the filter does what it should. I can't say whether yellowing is prevented, as I lack the knowledge here. The product makes a very good and professional impression on me.

Hope my review was useful.