I bought the Graduated Filter because it was recommended to me by friends.

After a few weeks in use, I can say that I am more than happy with it.
When photographing, it is necessary to darken the sky (e.g. at sunrise or sunset) so as not to get a burnt sky or too dark foreground.
Here the filter shows its strengths. The filter can be positioned very easily in the appropriate holder without the risk of slipping. This allows you to get beautiful photos even at long exposures.

For expansion I will add more filters of this brand later.

I can make a clear purchase recommendation!

Fast delivery. Good and nice packaging
There are many different connector adapters for all common lens sizes. The bays were a little too tight on delivery, but I unscrewed the screws a little and then it was ok. I didn't notice any color cings in the filters which I like

Absolutely delighted! K&F did a lot of things right here! When I unpacked the adapter rings and the holder, I was already very satisfied. Metal case from 48 to 82 rings. But then the glass, it is packed in a leather case, very high quality! This is otherwise only known from very large brands and companies, which can also be paid well for expensive money, but the price is right here! Only the German translation in the instructions leaves something to be desired! Doesn't flow into my rating! I can overlook that! Dear K&F team, please keep it up! An absolutely overwhelmed customer that you won with me!

A mild light reducer. Can be easily plugged in together with other medium-strength ND filters. Quality like other manufacturers offer. Good optical glass.

Great quality product at a great price, note these are all Hard Grads which is exactly what I wanted.

These filters work, especially in areas rich with sodium/mercury vapour lights, but don't expect total cancellation or miracles. It does help bring out details and colours in the night sky.
I accidentally lost an accessory, but it continues to work. the K&F team contacted me and insisted on sending a new one to make it right. I just received a new accessory yesterday. At least you know that they have good customer service and are willing to make things right for you.

I've been toying with the idea of ​​buying a graduated filter for a long time, although the prices from Nisi, Haida, etc., around 150 euros, have always put me off.
Then I came across the filters from K&F, because the filters were reasonably priced, I ordered them.
The extremely beautiful and high-quality packaging should also be emphasized. Here you get an imitation leather case that is lined with fine fabric on the inside and has 2 magnetic buttons incorporated. This case is again in a nice padded cardboard box, very valuable and stable so I wasn't really disappointed.

Filter holder:
First of all, it has to be said that you need a filter holder system for the filters, which costs around €25 at K&F. This is well made and serves its purpose. Here comes the filter holder in a padded cardboard box. The scope of delivery includes the filter holder and 8 adapters in the size 49mm - 82mm.

So I'm already looking forward to going out into nature with the filter to test it.
The adapter ring is screwed onto the lens thread and the holder is simply mounted on the ring with a snap mechanism. The mount holds securely and doesn't give me any concerns that it might not hold even with minimal play.
The optical quality of the gradient filter is great! I didn't notice any loss in image quality and there's no distortion or vignetting. Furthermore, I could not detect any color impairments or other color distortions. The filter does what it is supposed to do, it easily darkens an overexposed sky and saves me a lot of work in post-processing.

Conclusion
Since I haven't worked with ND filters before, I don't know what I could complain about here.
Overall, I am very satisfied with the glasses from K&F. You get a high-quality, processed filter with top optical quality and a good scope of delivery (artificial leather case). For the price of around €115, it doesn't need to hide behind the other brands. I will soon buy more glasses from K&F.

Of course, in preparation for our round trip, we also needed a good filter system. We spent months reading, getting information, watching and comparing videos. In the end we decided on this system. And that was a great decision! There are definitely better systems out there, but also for a lot more money. Everyone has to decide for themselves whether a hobby photographer really needs it. With this system, we are talking about real glass - not plastic! The glass is not colored but coated, so there are no distortions or blurring at the edges. The only drawback is that the glasses are quite difficult to slide into the holder - BUT nothing slips out and nothing slips. Perfect for quick position changes. We got used to it quickly. The results with the filter are as desired, there is nothing to complain about. We are thrilled and would choose this filter system again and again. We bought the kit with the holder including all adapter rings, the graduated filters, the 64 and the 1000 - everything was great! Have fun capturing memories!

Just recommend!! The filter system and the 10 stop ND filter works great.

the quality of these filters seems to be on par with others (more expensive ones). The course is clean and evenly straight. The very well thought-out pockets, with their pull-out tab, offer fingerprint-free handling. Clear purchase recommendation on my part...!!!