Use this with step down rings so I don't need one for every lens. K&F is my go-to for filters.

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.

These rings allow you to step up or step down the filter screw at the end of your lens, so that you can interchange filters for one size to anothe smaller of bigger one. Personally, in order to not end up with images that have circular borders, I would only work with 2mm differentials maximum on step down but if a larger filter should work OK on a smaller lens. Best advice is to try the various options with test images first in order to make sure.
In use they are fine but take care not to over tighten or cross thread when fitting.

Had cheap step up rings. Until one didn't settle on the lens and I couldn't get it off. the K&F Concept I've monitored even has grip teeth like this. and just feels secure, always removable and always stackable. I just think the price is a bit high. (I mean it's just a step up ring :D)

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** :)