nothing fancy about UV filters, you just don't want them to effect your shots, K&F's does a great job with their glass filters. When you invest 100s of dollars for a lens you want something to protect it without distorting and K&F filter do that.

I always get filters w/ non-slip design when it's available. It makes a huge difference. I compared it w/ Hoya HD2. I shot these w/ Canon M50 w/ Nikon 35-70mm f/2.8 AF ZOOM-NIKKOR.
1) No filter. 2) K&F. 3) Hoya HD2.
Sure, it's not a great test but I can't tell any difference between all 3 of them. The Hoya was optically as good as K&F except it was very staticky that I had to return it. I didn't like it's not non-slip either. The K&F is not staticky at all and very easy to clean. When there's no reflection, it looks like there's no glass inside the ring. Kind of like magic. It's very well made.
I use it on my Zeiss 50mm f/1.5 Sonnar T* ZM. There's no play and it fits perfectly. Very happy about the purchase.

Perfect fit for my Canon RF100-500mm L lens

Quick delivery, great product, works well.

Just received today. It feels light, even a bit flimsy when I hold it in my hand. Nevertheless, it feels quite high quality. It seems to have a thinner glass substrate compared to the B+W filters I have. Given the 95mm size, I even have a feeling that the glass might warp under stress, although I know that's unlikely. I'm curious about the optical performance. In terms of price, this is unbeatable, what all other UV filters should cost. There's just no justification for seeing a UV at $200 or even $300. Selling a UV for $200-300 sounds to me like people want the money but don't want to work reasonably hard.

needed to protect the lens on my FZ300 and this filter has some good reviews. The overall quality seems very good and the packaging works well when it's larger than necessary. The filter threads well without affecting hood fit, stows or deploys upside down and shows no vignetting at 25mm. There doesn't seem to be any noticeable degradation in photo quality. The glass seems to attract dust and had to be cleaned several times before I could attach it to the camera with no particles on the inside. The outside needs frequent brushing. I'll update if I find more issues in the future, but this filter seems like a good buy.

Just what the camera lens needed!

bought this for a rarely used camera. It's still a valuable collector's item that I want to keep in excellent condition and that means I had to protect the lens. I only have filters with the Zeiss "T" coating made of German Schott glass on the cameras that I use a lot because I think they are the best multi-coated filters I can afford, but I can't spend the money on them spend on a camera I rarely use. Any camera that is threaded to accept a filter deserves the protection that comes with a filter mounted in front of the actual camera lens. I would rather risk damaging the AR coating of a filter that can be easily replaced than risk damaging the actual lens on one of my cameras through cleaning and exposure to dust or chemicals in the air. This brand of filter came carefully packaged and the filter holder that comes with the filter is well designed and provides excellent protection for the filter when it is not on the camera lens as I am using a different type of filter. This filter has multiple AR coatings on both sides of the filter and after comparing the results of identical images taken with the same camera using this filter and one of my prized and now unaffordable Zeiss "T" filters, I can say I see no difference can the results. I'm sure an optical lab could document some differences, but in the real world I can't see any differences when comparing the test images I took with this filter and the Zeiss filters I've used. This design works so well that I am slowly replacing the older non-Zeiss filters I have on my older lenses and cameras with these newer designs.

I have no complaints about these filters. I run them on all my walkabout lenses that are carried around. Flare resistance is very good thanks to the coatings, and it's rare that I have to make an adjustment to a shot due to flare. The only exception was when I was taking photos in a museum, pointing up at objects near bright lights. But other than that, they clean well and let me walk without a lens cap for those candid shots.

first bought the K&F Nano series filter for one of my lenses. I believe it was for my Nikon 80-200mm F2.8 D ED lens. This lens produces really sharp images at a distance and is not a close focus lens, even noted by Nikon. I bought the lens used and it came with a dented UV filter. I got ghosting and when I removed the filter the ghosting was significantly reduced. I ended up buying several more for my other lenses. I also use B+W filters. Well-made filters too, but a little more expensive. The K&F is by no means a $100 filter, but for the price it does what I need it to do. I particularly like the grease and water-repellent nano-coating. Worked well when I was shooting at the beach. The sea fog is easy to remove without smudging. We really don't need UV filters anymore with digital because UV doesn't interfere with the sensor like it did with film. I just use them to avoid having to constantly clean the front elements of my lenses. I think keeping this to a minimum will prevent potentially scratching the element. I know there are a few schools of thought on this subject, but I just do what I'm comfortable with. From what I've read and can tell, the filter is glass and not plastic, which is nice these days. I have them on all my lenses now and am happy with them.