It's a UV filter. Screws on. Stays on. Protects the lens from smashes and such.

Not much to be said, I bought this to protect the lens glass more than for UV protection and it does as I wanted it to do.

I do a lot of hiking and use these UV lens mainly to protect my lens from scratches. The price is right and when they get scratched I put on another one. Saved a lot of camera lens using these

Faultless!The Neutral Density (ND) filters are wonderful and they do stop the light hitting the sensors no problem.The other filters are perfect too but normally you don't need a UV filter on a digital camera but I use it just to protect the lens.The other filters will them screw onto the UV filter but don't screw too tight.The polarised filter does have a revolving rim "GASP" and is ideal. I didn't realise it had a revolving rim until I actually used it and screwed it on.I can tell you now that anyone giving these filters and less than 5 stars are bonkers because these are superb.The wallets they came in are and look really well made as does the filters. The rubber lens shade is really good too and will push flat to allow it to fit in your case. I have no use for the plastic screw on shade so that will be used for something when I have my thinking head on.The lens cap is a good one and comes with a lanyard but I will not use the lanyard as I do not want it dangling from the camera.I would recommend these to anyone who want cheap but quality lenses.

We always get uv filters, primarily to act as protection for the lens itself. This one fits, so it does what we need.

I do not use these for the UV filter but as a good quality, low cost lens protector. That said:My 1st Tiffen was a 55mm UV Protector I got for the kit lens that came with a Sony a7ii; an FE 28-70. I was so happy with the purchase that I have since purchased three additional Tiffen UV Protection Filters. One is on a Sony E 55-210 I bought used and one is on a Samyang 35mm I bought new. The one I am writing this review for I assume is still on the Sony FE 50mm I bought new but returned and forgot to remove the filter.The point? I treat my lenses, new or used, like I treat a cell phone. That being the phone stays in the box until I have a protective case for them and lenses stay in the box until I have a protective filter to pair them with. And the one I forgot to remove from the returned lens? That is how confident in the Tiffen filters I am. Once I put one on a lens, I never need to think about it again.I have used several brands in several sizes ranging from the cheaper Altura and Polaroid to the mid range Hoya and B & W.Where does Tiffen fit? Well they are no Hoya or B & W but I am no professional photographer. I am an amateur who mostly enjoys street photography when I travel and for my money Tiffen is the best. Yes, you can spend more and get better glass and if you really have reason to worry about ghosting you should look for a higher end lens. That isn't me saying ghosting has been a problem for me. I normally use a lens hood and I think that helps cut down on light reflection. I have noticed some minor issues with it on some shots I have taken in direct bright light conditions but not enough to justify the higher price.I do not stack filters as I haven't had a need to so I can not give an opinion on that topic. I would assume that the risk of ghosting would increase.The short version is this. The Tiffen UV Protection Filter is well made with good quality glass and a metal ring with threading I do not worry will cross thread or strip. They do what I need by protecting my lens. If I was buying a ND or polarizers I might buy a more costly brand but for everyday protection, Tiffen is all I need and the best for my money.Tiffen say it best in their own product description; A small price to pay to protect your investment.

Good to have this as it doubles up as dust protection for lens apart from being a UV filter

I first purchased 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. That lens produces really sharp images at distance and is not a close focus lens, even noted by Nikon. I bought the lens used and it came with a beat up UV filter. I was getting 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 too. Well made filters as well, but a little more costly. The K&F is by no means a $100 filter, but for the price it does what I need. I especially like the nano-coating that resists grease and water. Worked well when I was photographing at the beach. Easy to clean the sea mist off without smearing. We really do not need UV filters anymore with digital since UV does not interfere with the sensor like it did with film. I simply use them to keep from having to clean the front elements of my lenses all the time. I feel reducing that to a minimum will prevent potentially scratching the element. I know there are a few schools of thought on this topic, but I just do what I am comfortable with. From what I 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 happy with them.