What I like about this filter set:
1) The filters themselves are good. I don't see uneven brightness or color distribution on the images
2) I tested it on a Nikon lens with 67mm thread. The adapter ring fits it perfectly. But this is also where the problem comes. I already have a UV filter on the lens. With this ring on, it causes a minor dark corners. With the filters on, the dark corners become more pronounced. I could remove the UV filter, or what I really should do was to order a larger set and then use a step-down ring.
3) The magnet works really well
4) The package is nice and well-thought. It has a belt clip and D ring that allow you to either carry the package on your belt or hang it on the tripod or backpack.

Overall, this is a convinient package of filters that are easy to use. Just be aware of choosing a right size for your situations.

I am not an expert in photography but I am very happy with this quality polarizing filter kit. Very easy and quick to install on the lens. It works by a main ring that is screwed to the lens, once this step is done just position the magnetic filters on it. It's really practical, I think it's great. The cork is also very pretty. The storage bag that comes with these filters is nice and can be easily attached to a belt. The filters are really good. I am very happy with it.

Great set similar to my free well that I got from a few years ago. These are not variable so there is no cast in the photos when you take them. They are just solid darkness and they are magnetic so you can swap or stack them on top of each. The magnet cover doesn't go over a hood but they work nicely with the cpl on my 70-200 lens. Great to use it during the bright days with a hood on which is the only set I found that allows me to use it with a 70-200 with a hood on. You have to find a thin thread that fits in the 77mm size of the 70-200 and be able to attach the hood on.

I am very happy with this K&F Concept (77mm) magnetic filter kit. The carry bag is very nice and the 3 filters are all high quality (CPL, ND8, ND64) along with the magnetic basic ring and lens cap. The magnetic attachment method is so convenient to switch out filters so now I am spoiled. I think I want to get the ND16 and ND32 and maybe the VND as well. The filters are stackable so could get almost ND10 if you used the CPL and ND8 together or higher with other combos. The filters work great on both my Panasonic 10-25mm f/1.7 and 25-50mm f1.7 77mm lenses. The magnets are strong but just like your normal lens cap the filters can be knocked off if you happen to bump the end of your lens. So don't do that... lol. These filters are a good purchase.

The K&F Concept neutral density (ND) and circular polarizer (CPL) magnetic filter kit contains two ND filters, one for 8 stops, the other for 64 stops; a CPL filter; a threaded magnetic filter-holder ring, and a magnetic lens cover. The kit includes a padded bag to protect and hold the filters.

I ordered the kit with 82mm filters. The magnetic attachment is great for easily interchanging the filters. No need to unscrew a filter and then realign threads to reattach a different filter. You simply firmly tug on a filter to remove it, and then magnetically attach a different filter. Very simple and the filters are firmly held in place – no concerns about them accidentally detaching. The lens cover can be placed over any of the filters, so no need to remove a filter before putting the lens cover on. In addition, I was able to place the “pinch-style” cover that came with my lens on over the filters also, providing another option. Like the magnetic lens cover, the magnetic filters can stack on top of each other, but the filters are not threaded, so a threaded filter cannot be placed over the magnetic filters. The magnetic base allows the circular polarizer to rotate easily, while still providing a secure attachment to the lens. The filters worked well – the polarizer worked great to eliminate reflections, etc. and both ND filters allowed opening the aperture several more stops, reducing depth of field. (See included photo examples.) I have K&F Concep filters on two other lenses and have been very happy with those products. Likewise, I am very happy with how these magnetic filters worked on my camera.

I normally have a K&F 82mm threaded UV filter on my lens for protection. My only wish is the filter kit also included a UV filter or skylight filter that I could leave in place on the lens. As it sits now, I need to unscrew the UV filter and screw on the magnetic ring whenever I switch to an ND or CPL filter. I am shortly orderly a K&F Concept magnetic mount UV filter to avoid this cumbersome switch.

I've decided to switch out my screw on filters for magnetic ones and this K&F Concept neutral density and circular polarizer kit is a versatile and great quality way to start.

The magnetic base screws on securely and it's so easy now to change filters on the go. Yet the filters stay on so well. They stack easily as well, something I tended to avoid in the past due to filters often getting stuck.

This set has really given me more freedom to experiment with different filters and combinations. I'm not noticing any objectionable color casts and the glass is extremely smooth. The metal is beautifully finished.

I've been able to use the included magnetic cap or a standard pinch type cap. The included storage case is super nice and convenient, I'd like to order another to contain additional filters. The whole kit is a great value.

This filter set works well for hot swapping. The magnets are quite strong and hold the cap and filters nicely. The CPL turns smoothly, and even though it's magnetized works great. The ND filters require no turning and simply snap in place. You can even stack them! They all fit inside a well constructed case with a magnetic flap and weathersealed zippers

The only con I noticed, I was unable to thread on a non-magnetized filter to the magnetic mount. Therefor, you are locked into using this system unless you remove the magnetic base. It's just like how I used filters before so it's really no big deal. All in all, this is an uprade I will be using all of the time now.

I suspect that anyone who has employed screw-on filters has wrestled with the joy of removing them, especially when dealing with dissimilar metals (different coefficients of expansion). This magnet system eliminates that fight.

As in the case of all of the K&F filters I have obtained, this kit appears to be superlative. Visually, the glass is flawless, the density and coatings are even, and the slim mounting rings lessen the possibility of vignetting when stacked. The hook-and-loop or D-ring make for convenient carry and, because the filters are magnetic, I store them stacked which leaves the other pockets available for other filters.

So, a nice concept with excellent filters and, for three filters and a lens cap, a reasonable price.

Though I'm no expert on glass and coatings, I found the glass to be clear and without any aberrations.
-The 3 filters, ND 8, ND64, and CPL/UV, are a good combination for different shot scenarios.
-The amount of magnetism is just right. Filters don't fall off, yet they come off easily when removed.
-With the screw-on mounting ring and a filter attached, no vignetting was observed.
-It comes with a good padded case with a velcro belt attachment and a ring for hanging off a bag or backpack.
-The magnetic lens cap is much easier to apply than normal spring-loaded caps.

This is a great little kit at a very reasonable price. Recommended.

The magnet is fairly strong and is not falling off.
The filters color cast is very minimal and the sharpness is not affected by the filter as far I can tell.