K/F Concept is a brand of photography accessories, which is especially known for its quality/price ratio. I have several things, and I can say from the outset that in general they are very good in terms of the aforementioned star relationship.

We received a small box that is basically the size of the filter box itself. Well, it's actually the plastic filter cover with a silver cardboard cover on the outside. It arrives sealed in transparent plastic, which guarantees no prior manipulation. The box also mentions that it is "slim" (to avoid vignetting and that we "see" the filter in our photos), that it has a multi-layer filter and that it is water resistant.

It has metallic orange levers on opposite sides. It fits very fine and is very comfortable.

A vacuum-packed microfiber cloth is included. Which is suitable for all types of lenses apart from the filter, also for glasses, lenses, etc...

My version of the filter is with a 72mm thread pitch, to be used mainly on my 135mm F2L. Incidentally, most Canon L series lenses are compatible with this filter size.

The filter from ND2 to ND32 varies depending on how we turn the screw. What it does is darken the image progressively, without generating banding or noticeable defects (at least in my tests). Normally you will want to darken the image if you want to take longer exposures without burning the photo, such as in a classic silk effect of water coming down from the river. Another use of darkening the image is when you want to shoot with a very large aperture but even if you lower the ISO to the minimum there is still too much light. This second option is the one I had in mind for my lens: portraits at f2.8 with solaco