The K&F Concept 49mm Circular Polarizing Filter with Filter Cap Optical Glass Ultra Thin Polarizing CPL Polarizer Filter with 24 Multilayer Coatings for Camera Lens (D Series) is well made and feels like good quality. It's a great product for the money.

The K&F Concept 49mm MC UV Lens Protection Filter is well made and easy to use. Feels lightweight but great quality. It’s a great product.

The K&F Concept Nano-X True Color ND Filter 49mm Polarizing Filter&ND2-ND32 arrived quickly.

It is very neatly and safely packaged.

The filter is of very good quality. Very high quality materials. Great workmanship.
The settings can be adjusted continuously using the small red handle on the edge.

With its 49mm, it fits exactly on my kit lens. If you have lenses with a larger diameter, you should choose a correspondingly larger filter.
I still have to practice using the filter correctly. But I am already very impressed.

The 49mm ND filter came in a typical filter case along with three pieces of microfiber cloth.

The filter looks well made. Clear markings on the filter and so easy to rotate and set it to the desired setting. It is easy to mount the filter onto the lens and remove it. The lens cap fits over the filter just fine.

I shot quite a few images, the light gathered by the lens is reduced as the filter ring is rotated to a higher stop. Happy with the results for occasional use. I can use this filter for long exposure to get say motion blur. My initial review with some shots of the trees showing the light reduction got rejected and so not including them this time.

I bought the K&F Concept Variable ND Filter Neutral Density ND2-ND400 (9 apertures) with rotating ring to be able to use a fast ND with different densities. The packaging is very well made, solid and space-saving packaging. The glass filter is light and the density increase / decrease ring is liquid. It does not have a limit switch block.

The "K&F Concept Nano-X ND Filter 77mm" comes in elegant packaging, which is easy to open and you can carefully remove the filter. The bag that goes with it is well made, everything looks very classy and you can expect that for the price. The filter itself is of very high quality and you can see all the key figures directly. Furthermore, it has two brass noses, which can be easily adjusted. Here you always have a good feeling and you overshoot (turns too fast) or too slow, but you always have the right feeling when adjusting. The resistance here is just fantastic. The image that can be conjured up from the filter is simply overwhelming and is worth its price. Here it makes no difference whether you have sun in the picture or are completely blinded,

I received this K&F Concept 58mm ND8 Lens Filter (3 f-stops), Fixed ND Filter with Double Sided HD 18 Layers Multilayer, Ultra Thin Optical Mount, Nano-X Series for Lensless Camera Lens in the Amazon wine program. Generate reviews on new products to be heard on Amazon. ND filters are designed to take long exposures and not overexpose photos or change colors. The filter also reduces the intensity of all wavelengths of light without changing the hue of the color rendering. It filters to reduce the amount of light entering the lens. This allows us to choose combinations of aperture, exposure time and sensor sensitivity that would otherwise produce overexposed images. There are difficult ND filters to control the amount of light entering the camera, that's three stops. This K&F Concept ND8 filter is well made and works well. I've only filmed it once so far, but it was very cool. These are a must have for any Phoargophère amateur or professional. I can highly recommend.

The K&F Concept ND Filter does not have a stop, it will continue to spin all the way around. Though it does spin freely, taking the camer in and out of a bag/case may change the filter intensity. Otherwise it allows for much lower f stop. I use this while filming outdoor shots.