The filter I always stack are CP and ND, and now I finally have them in 1 filter!
ND and CP effects are both very nice, and the filter is built solid.
K&F makes some really nice stuff.
All threads are smooth and the filter is easy to install and adjust.
It's been on the front of my favorite lens since I got it, and it makes my vids look professional.

I picked this up to use with my Sony A6400 with Sigma 30mm 1.4. This is my go-to set-up for taking pictures of the family/kids but wanted this filter to be able to shoot wide-ish open during the middle of the day. So, basically it does exactly what it's supposed to do; there wasn't any noticeable distortion, softening or color changes, and it was able to drop my shutter speed enough to not blow out the highlights. What I really like is the knobs that allow you to change the ND intensity quickly - this is an absolute life-saver for shooting toddlers and young kids, as they are the fastest things on the planet and they're not going to wait for you to change the filter on your camera. The only negative is the need to potentially get a new lens cap as the filter diameter is larger than the lens cap diameter. This is addressed in the description, but it's just something to keep in mind. Overall though, it's a nice filter.

I'm positive I picked the proper size filter but it came with a smaller one. Since I only have one lens that I can adapt it to I won't be able to use it with the lenses I had intended to use it with. I like the concept of the combined ND and CPL Filter I know I can stack filters to get the same result. But it would have been nice to have the two things in just one lens filter. The polarized lens It's very often handy to have for longer exposures Regardless that It's not the size I wanted you should be happy with the results you could get from this combination. I have always been happy with K&F filters

The price is reasonable, and I think there are many advantages, such as the thin frame and the feature to combine with the cpl filter. Works with my camera perfectly and no problem so far.

The ND2 – ND32 (1 – 5 stop) variable ND filter is an essential filter for capturing outdoor video footage, and the K&F Concept combines it with the mostly used filter for every photographers, the circular. This becomes one of my best accessory for my camera. It saves so much time and effort. I'm very happy with this purchase and will consider to buy from K&F Concept again if I need other accessory for my camera.

With no visible X or color cast, I'd say this is a good VND filter.

This CPL ND filter is awesome. The build quality on this filter is immaculate. The threading is all metal and just glides. Theres no annoying X pattern on the ND side of things and it does an excellent job at getting rid of unwanted reflections as well. The optics are also excellent there is no dip in quality and the coatings really help to cut out glare and purple fringing.

I'm just an amateur photographer, but I really like this filter. It's like having two filters in one. The adjustable ND filter means that I don't have to keep switching out filters when taking photos. The filter is well made and works smoothly. It comes with a sturdy plastic case to keep the filter in when not in use.

Very good filter, the quality is there.
Very practical to have both filters at the same time.
Very practical to be able to also modify the ND filter thanks to the variation ring

I recently purchased this product and I have to say that I am extremely satisfied. There are several positive aspects that deserve to be highlighted.

First of all, no color cast: this is a fundamental aspect, especially for those like me who appreciate color fidelity. The images are natural and realistic, without any unwanted nuances that could alter the original colors.

Secondly, the construction of the product is excellent. The materials used are of high quality, solid and resistant, which contributes to a feeling of robustness and durability over time. Every detail seems to have been taken care of with great attention, and this is reflected in the user experience.

Finally, it is an extremely comfortable product to use. Ergonomics was clearly a focal point in the design, which makes it easy to handle even during prolonged sessions. The controls are intuitive and well-placed, allowing for smooth and effortless use.

I use it for my work as a videographer, and I must say that ND filters are absolutely essential to maintain a correct shutter speed, especially in very bright conditions. This product has proven to be up to my expectations, allowing me to obtain high-quality shots without compromise.

In conclusion, I highly recommend this product to anyone looking for quality and reliability. A purchase that certainly does not disappoint!