The filter arrived well packaged and on time, as usual, at my home. The filter is delivered in a protective box and a cleaning cloth. The filter box is designed for much larger filters (I estimate 82 mm) and doesn't have a suitable cutout for this 67 mm filter. This not only makes the box significantly larger than necessary, but the filter also rattles around during transport. Solution: use your own filter bag, in the right size. If you're familiar with K&F, you don't need to say much about the quality. The materials and workmanship are excellent, and the image quality is also flawless. The different price levels at K&F correspond to better coatings. The K series is obviously inferior to the X series, for example, but also somewhat cheaper. And for most people, the K series will be sufficient, as they are already 18-layer coated, thus also repelling water and dirt well, are easy to clean, and enable outstanding image quality. The filter is quickly screwed onto the appropriate lens. In my case, it's a Canon RF 24-105 f/4. Thanks to its excellent and precise workmanship, the filter also provides perfect dust and scratch protection. Filters generally have a negative impact on image quality; the question is, how much? This filter is very inexpensive at around €20 (67 mm), and I find the quality to be decent. Flares (backlighting that causes unwanted reflections within the lens) seem significantly stronger to me, but that really depends on the lens, and a lens hood is always better than a better filter, unless you can avoid flares or even intentionally use them. A great filter without any loss of quality.