The adapter rings allow us to place the filter holder on any lens, as we have a large number of different diameters. They are made of black metal and well finished. With labeling on each ring with the corresponding diameter.The filter holder is metallic with the part where the filters go from a kind of hard plastic. Two 100x100 filters fit and 100x150mm gradients without any problems. The attachment system to the adapter ring is via a very manageable metal tab.In several tests I did under different lighting conditions, I did not notice the entry of residual light through the space between the filter and the filter holder. The photos have a slight magenta tint that is very easy to correct when editing, but it is not at all overdone. I am very pleased and enjoy it very much. I recommend it!

I had never owned a K&F Concept filter before and was pleasantly surprised when I first used it in my landscape photography. The reverse graded ND filters of the popular brands of photo filters tend to be quite expensive and this one in particular is more affordable and achieves results that match and even better than the most reputable filter brands. It's made of glass, which is an advantage over resin filters as it doesn't scratch easily. I really liked the filter cover, which is made of leather with inner protection. In short, I really liked this filter and I am sure that I will use it very often in my landscape shots.

Everything as described. A great system.

I have long played with the idea of buying a graduated filter, but the prices of Nisi, Haida, etc. around 150 euros have always deterred me. Then I came across the filters of K&F, since the filter was in a Preislich favorable frame I ordered them.

An accessory with variable applications, the case is best

outstanding box and quality.
I would like to see in future a GND 100x150 soft 2 stop

Good quality of the filter.

This is tough to beat. Not only do you get a 100mm GLASS (not plastic) 10-stop ND filter, but you also get the filter METAL mount and multiple METAL lens adapters. Even if you need to buy step-up/down adapters because the ones included do not fit your lenses, this is still a bargain. Even though this comes in at well below the price of other 100mm 10-stop filters (without the mounting system), it performs excellently.

My unit doesn't produce any noticeable color cast, but I also shoot solely in RAW, so a color cast wouldn't be an issue anyway. The case for the filter is firm, so I don't worry about it very much when it's in my camera back, and the soft lining keeps the filter safe from scratches (so long as nothing coarse gets inside, of course). Better still, the filter mount features a second slot should you wish to use additional 100mm filters (e.g. graduated filters). I point out the size because this is the "standard" in these filters, rather than the more common 80-something mm ones you see in comparably-priced square ND filter bundles that use smaller, cheaper plastic filters instead.

The only issue I found, and this is really just nitpicking at this point, is that the filter mount never really feels very securely attached to the lens. The filter and mount won't fall off if the camera is moved or tilted forward, but the mechanism that attaches the mount to the lens adapter could be a bit tighter fitting in my opinion. Nevertheless, great product at a great price. Anything "better" will be considerably more expensive, and even then, how much "better" will it be?

These filters are an absolute highlight, convincingly good quality, everything fits perfectly, everything packed in high quality and protected for transport in beautiful cases.

It is an excellent quality item, it allows you to take pictures with very slow shutter speeds, and the effects are incredible. Very happy