K&F Neutral Density Variable Filter is a good product is well made, it's durable and it fits well onto the lens. The product was as advertised no vignettes which was important for me since another ND filter I purchased in the past created a vignette problem in my photos. I'm pleased with my purchased and I definitely recommend this product. The only thing is that I wish it would have been a 10 stops ND filter instead of 5 stops.
77mm ND2-ND32 Variable Neutral Density ND Filter Nano Coated
This is a nicely made 77mm neutral density filter with the added feature of being variable (ND2 to ND32). It has an aluminum frame which is a common metal used for lens filters. It works well to cut light and allowed me to take better pictures in brightly lit environments. A filter to add to my kit and useful for me especially for landscape photography.