decided to try this ND2-2000 filter from K&F Concept in the 49mm diameter size for my 35mm f/1.8 lens mounted on the Sony ZV-E10. The filter in question offers a wide range of stops between ND2 and ND2000, allowing for great versatility in both photography and video. In photography it is very useful for obtaining long shutter speeds even in broad daylight, for example to capture the silk effect on water, while in video it is essential for compensating for excessively high exposures while maintaining the same aperture and depth of field. The build quality is excellent: the glass used is top quality, while the nano coating improves its performance by reducing reflections to a minimum, furthermore, the surface always remains clean. I was positively impressed by the very reduced thickness of the filter, just 7.4mm, which does not add weight to the equipment, the thread is precise and allows for quick assembly/disassembly. I would just like to point out that the ring travel to change the intensity of the filter does not have any type of stop, therefore it rotates infinitely on itself, therefore I recommend always checking exactly at which stop it is positioned before taking a shot or filming. Overall, it is a reliable and well-built variable ND filter, which due to its characteristics is extremely versatile for both photography and video. At 49mm it was a good purchase for my 35mm lens, and I recommend it to anyone looking for a complete and excellent quality product.