K&F is one of the most underrated brands in photography/videography. Because they are value-priced, the You-Tubers out there turn their nose up at this brand while they hawk more expensive brands through their affiliate links, but after owning and using a half dozen K&F filters, I'm a convert. I had purchased a Tilta Mirage matte box, with the intention of using a large-format variable ND filter, but while the matte box looked impressive, I realize that it was more of a hassle than it was worth just to "look cool", so I was looking for a screw-on variable ND and settled on the K&F concept. As advertised, it delivers 5 full stops of exposure control and, most importantly, does so without the dreaded "X" that is a frequent problem with cheaper filters. I did a comparison using the Tilta Mirage variable ND and the K&F filter, and there was no visible difference in qualtiy.

When I ordered this filter, I was unaware of the magnetic mounting system, and I have to say that I am now spoiled forever. With the magnetic ring srewed on, mounting and unmounting the filter takes just a second. I wish more filter manufacturers would use this system.

The price to qualify ratio for this filter is excellent.