I'm really digging these new filters that K&F are releasing. The magnetic filter system is a great idea for strong ND filters because I often need to compose my shot without the ND filter attached (because it's much easier to see through the lens without it) and then attach it to take the shot; being able to simply snap the filter on to the front of the lens takes a lot of the hassle out of detaching and reattaching the filter.

The optical quality is superb, with excellent clarity and barely any color cast. The build quality of the metal rings is solid; they are smoothly machined with smooth edges and nice knurling. The rotating ND filter turns smoothly, with hard stops at either end of the spectrum so you know when you've reached the limits.

The magnetic attachment holds the filter in place snugly but it's probably best used in controlled tripod setups where you know the lens won't be bumped; I definitely wouldn't use this in any kind of crowd situation where someone or something could knock the filter off, because it wouldn't take much of a bump to cause this to happen.

There's no lens cap included, presumably because the extra weight of it would make the filter too heavy for the magnets to comfortably hold. K&F does make a magnetic lens cap, which I got with a different K&F filter set, but it doesn't fit on the outside of the ND filter because the outer ring is larger than 77mm. However, the magnetic lens cap DOES fit on the inner ring so you could use it when you're not using the ND filter. As far as I can tell you can't buy the magnetic lens cap by itself, only bundled with other filters.

This filter is easily comparable in quality to those made by Tiffen. It's fairly priced, and I would definitely recommend it for tripod-based landscape photography.

Have no issues and does what it needs to. Seems like good quality so far

I did not notice loss of quality. Happy with result.

Easy on, easy off, good pictures, no vignetting, great value.

But I think I'll need to go higher than 32ND, though it is of excellent quality I can't seem to get a really long exposure with these. may need to go up to 400 to see the differences.

The magnetic lens system is the absolute best for me, the lens quality is good. I am very satisfied.

Efficient. Great adjustment/setting control. A tad expensive. Great filter case.

It does the job BUT can't help but wonder if I should have gone with B+W's. For the price, it's good.

It really full feel all my needs, it works perfectly even in low light conditions I don't have to take it off, it is light enough, and also works perfectly in bright sunlight, no flares or vignetting, it arrived on time and shape. highly recommended

So I purchased both the 2-5 and 3-8 stop and they both are so clutch. I literally have no issues going out on a bright day to shoot stills or video with these two in my arsenal. I’ll be taking them down to Vegas next month so I’ll get a real test, but for now these are the best. I love the hard stop.