You never want to be without protection, so it's a good idea to always have an extra UV filter on hand! I have a few other K&F's including UV and polarizer and have no problem recommending them. I saw no anomalies, flares or distortions.

There is no chromatic aberration, the polarization effect is obvious, and the customer service is also very professional, which is highly praised

The filter itself seems fine, but as for the packaging, the cardboard didn't tear where it should, I had to rip the cardboard apart, and as for the metal container holding the filter, it took me fifteen minutes and two knives, to open it

This one is better on cloudy days.
I have several polarizing filters from K & F. I think they have made me a better photographer.
It's been snowing lately. I wanted to take photos of the untouched snow. The sun came out and the shine was reflected in the snow. This filter toned down the glare and gave much better shots.
Now, without this filter and my black K&F filter, I never head out to the day.

Fast delivery, typical CPL packaging in the plastic box, nothing special until then.

Very good anti-reflective coating without loss of sharpness with the CPL 55mm diameter D series. I've always lacked that little bit of sharpness, even that was remedied by, among other things, higher-contrast imaging.
The picture uploaded here shows a 100% crop on the left without a filter and on the right with a filter. I was concerned here with the sharpness image, made with a Sony a7ii and a kit lens on 65mm with 1/100 f5.6 ISO 800. The second picture
shows left without reflection and right with reflection.
I didn't want to try if it was scratch resistant.

The processing of the lens is good, the material is there and the polarization effect is still very clear. When photographing mirrors and windows, the reflection is obviously filtered out. I haven't tried the scenery yet. I will check it later try it.

Had previously ordered the filter from AmazonBasic, but unfortunately it blurs my Sony 135GM F1.8 as if it were a much cheaper lens. The KF is sharp, and costs about 2.3 times more at ISO, quite normal and at F1.8 often very desirable in daylight. It's very flat, which in itself is a good thing. The only thing is that the lens cap does not hold as well as it should. Rotatability is ok, steady but a bit heavy. You should get yourself a pull-off tool, without it the filter is often difficult to remove. Filter effect at the lake was ok, but of course not all reflections go away, that would be against physics. So overall I'm very satisfied.
Small addendum: The filter has a slight brown/yellow tinge, which is already noticeable in the sky. The corrugation when turning is good. If you have a good lens, you should not skimp on the filter. Possibly better a good one in 82mm and then adapter rings.

I compare this to the Bower Digital PL. It's 1/2 the thickness and easier to use because the rotating part has ribs placed around it, giving you a good grip and controlling the polarization. I tested it today and it appears to be completely color neutral and no color fringing like I've seen others do. The price is right and I can only recommend it.

I ordered this polarizing filter to use with my Sigma 30mm F1.4 DC DN Contemporary lens (my prime lens, not included). Polarizing filters eliminate non-metallic reflections, improving scene detail and contrast. This is a top quality polarizing filter whose polarizing effect can be easily checked by rotating it while viewing an LCD monitor through the filter. The filter has multiple coatings to prevent annoying optical reflections from appearing in photos. The filter processing is excellent: the threads attach cleanly; the filter rotates smoothly when the lens is mounted. And the robust plastic filter container lined with foam effectively protects the filter

This is the first lens filter I have ever used. I've always read/heard that a good filter can make a significant difference, but until now I've never gotten one. This polarizing filter is very nice! The high-quality construction of glass and metal is easy to see. In my pictures you can see that the filter is attached to my camera, but I was able to attach my lens hood directly to the front of the filter. It has front pickup threads in addition to the rear threads. A really nice feature is that the front of this filter rotates freely. This way I can now easily rotate the tulip hood to the best position without the risk of the filter or hood loosening. I couldn't do that when the hood was connected directly to the camera. But does the filter make a difference? I am happy to say that it works very well! I often take pictures through a window and it's very common for the picture to have some "haze" that wasn't there when I took the same picture outside. I took a picture through the window with this filter and was pleasantly surprised to see a picture that looked like I took it outside. I don't know exactly how this works, but it does. Just like polarized sunglasses, this filter "steers" the light in a way that enhances what you see. I am impressed! I often take pictures through a window and it's very common for the picture to have some "haze" that wasn't there when I took the same picture outside. I took a picture through the window with this filter and was pleasantly surprised to see a picture that looked like I took it outside. I don't know exactly how this works, but it does. Just like polarized sunglasses, this filter "steers" the light in a way that enhances what you see. I am impressed! I often take pictures through a window and it's very common for the picture to have some "haze" that wasn't there when I took the same picture outside. I took a picture through the window with this filter and was pleasantly surprised to see a picture that looked like I took it outside. I don't know exactly how this works, but it does. Just like polarized sunglasses, this filter "steers" the light in a way that enhances what you see. I am impressed! I don't know exactly how this works, but it does. Just like polarized sunglasses, this filter "steers" the light in a way that improves what you see. I am impressed! I don't know exactly how this works, but it does. Just like polarized sunglasses, this filter "steers" the light in a way that improves what you see. I am impressed!