My first experience with the K&F Concept filters was with the purchase of a light pollution filter I've been happy with, particularly liking the grippy knurl added to the edges of the filter. After accidentally scratching my Hoya NXT Pls CPL 82mm filter which is more than double the cost of the K&F filter, I decided to purchase the K&F Nano Series CPL filter and see how I like it. Moreover, I also chose to go ahead and buy a 95mm version as well, to replace a Pro Optics (Adorama house brand) filter that I thought might be a lesser quality filter. Both K&F filters arrived today and a visual inspection of them reflects a quality product as I expected. However, one minor complaint is that I like the round K&F filter case which as a rigid plastic insert that appears to be grooved to support holding any of various sizes of filters securely in place in the case....that is, perhaps for a range of filter sizes, K&F may be using the same case to save manufacturing costs. However, while the 82mm filter arrived with that same case, the 95mm filter was in a more common, square plastic case with foam cutout to hold the filter. Still fully functional, just not as nice as the case provided for the 82mm filter. I don't expect to see any problems with the cheaper case, but it is the type that frequent use could find the plastic hinge wearing out eventually; I simply favor the 2-piece round case of the smaller filter.