I've been a fan of K&F filters and accessories for some time now and have come to appreciate the brand's durability and quality. Most of my lenses live their lives with K&F UV protection filters on the front. Like many others, I've started to focus more energy on taking advantage of these features, not to mention portability, as the quality of mobile phone images and videos has improved to near-professional quality levels. In both videography and photography, whether with a full-size camera or a high-end mobile phone, I find a CPL filter indispensable. It also has the effect of neutral density. In the hand, the K&F Concepts Magnetic Circular Polarizing Filter System gives the impression of quality. Between the matte black finish, the 52mm magnetic adapter ring, and the reflection of the rich multi-coatings, it's an impressive filter. Interestingly, despite the fact that the adapter and filter are magnetically attached, the CPL still rotates freely as needed to adjust the angle. That must be magic. The only disappointment with the system for me is the lack of usable threads on the front of the CPL. I prefer lens hoods and would love a way to attach them. Or to have the option to mount another filter or step-up ring onto the system. However, step-up/down rings with appropriate 52mm thread can be attached to the threaded adapter ring. For example, a 49mm — 52mm step-down ring allows the 52mm CPL to be used on a 49mm threaded lens. On the other hand, the lens I showed in the pictures takes 52mm filters and its built-in sunshade fits well with the 52mm K&F Concept Magnetic System, but the lens' front cap does not. I checked the K&F Concept store and they have a number of other magnetic filters, filter sizes and adapter ring combinations in their magnetic ecosystem, most of which include a magnetically attachable front lens cap, including circular polarizers; why they don't include one with that combination I wouldn't know, but I think they should. The convenience of the system is negated if, to protect the font of my lens, I have to twist out the adapter ring to put it on a lens cap. I didn't notice anywhere in their Amazon store that a compatible magnetic lens cap is sold separately. In my view, a complete system, and I'm not just referring to K&F Concept in this regard, would include magnetically attachable lens caps and lens hoods as part of the ecosystem. Or failing that, the front threads on the attached filter or the corresponding adapter rings that are the same size as the rear threads on the adapter, allowing for a more versatile system and one that would accommodate the screw-on filters currently used by users. In any case, I have full confidence in the quality of K&F Concepts filters and their products in general. They are a reliable company that stands behind their product lines. If you are interested in any magnetic filtration system, including this one, I suggest checking out the K&F Concept Amazon store for all the available options. Enjoy.

They screw on pretty smooth it have a quality threads, and it work just fine. Perfect for someone who's only going to be casually using their step up rings, I am a professional photographer & I was looking same filter Ring Adapter & I order this product which is very helpful for me when I use multiple filter with my Nikon 5300 camera lens. During photo-shoot many time we have to change camera lens along with filter also, so using this ring it is very helpful for me, these rings get there job done, and don't get stuck. Please note - these are step-Up rings also have Step Down Rings total 18 rings.

What more can I say, the Step Up Ring is 1A compatible with my Canon Eos 600D (see picture). It fits like a glove, the zoom can be adjusted perfectly and a polarizing filter can be screwed or clicked on. But does the metal material keep what it promises??? But for around €7 you can't complain :-)

ordered the K&F Concept Step Up Ring 72mm to 77mm to be able to use my 77 filter as well. The ring is cleanly processed and the threads are cut absolutely cleanly, so it can be screwed onto the lens and the 77 filter onto the ring without any problems. No complaints, everything great. I definitely recommend the ring.

The Step-Up Converter Ring was packaged well and shipped quickly. So far I'm pretty happy with the build quality. The ring is made entirely of metal and seems sturdy to me. In addition, the internal and external thread is properly worked. Thus, the adapter can be easily screwed onto lenses. With the help of the adapter ring, I can now easily use my larger ND filter on my smaller lens. Everything works without any problems, which is why I can finally recommend the adapter ring.

K&F Concept Step Up Ring for lenses, 58mm to 62mm, just under 5€ With adapter rings, only the precision of the production counts so that the threads mesh well. The ring from K&F Concept fulfills this very well. Now I can also use the filters from my 55-200mm tele. You should only note that if you leave the adapter on the lens, you may need a larger lens cap, as the smaller one no longer grips. Conclusion: Everything in order, price is right. 5 Stars

It is a variable and polarizing ND filter.
The ND is 5 steps, there are 2 steps, 10 steps (ND1000, 1024 to be exact).
The polarizing filter eliminates light reflections on surfaces, cars, water, glass and also enhances the colors of the sky, leaves, asphalt, etc... (for more information search the web) Personally, I use it for video so as not to reduce the depth of field by closing

the Losing membrane (f9 further, I can now go to f2.3 without burning the frames from excess light). Haven't removed it from my 35mm in a while, I love it.

The filter is made of metal and glass, presented in a hard plastic case for storage. The protective and anti-glare layers of a greenish color are appreciated and you can put the lace on top that holds quite well without staining.
The lever changes the density of the filter and the other ring moves the polarizing filter. You need to pay attention because you can move both carefree.

In the pictures you can see the filter attached to an adapter, (Step-Up 49mm to 67mm) this is because I have filters of 67 and 49, my advice is to buy big filters and then "Step-Up" adapters.

About the picture quality. Excellent: There are no dominants, no chromatic aberration, no loss of definition, no appearance of the gradual ND filters' terrible X.
I have a very expensive polarizing filter and I hardly notice the difference with this one.

As a negative point, although I said before, be careful when handling one of the rings so as not to move the opposite.

**If it was helpful to you, remember to upvote so we can help each other** :)

Normal step up ring that works