own a few filters (UV, ND & CPL) and other products from K&F. This UV filter came in a square plastic case with a lens cap and lens holder. The filter was clean out of the box. I got this filter for my Nikon 20mm F2.8d lens. So far I have been using the lens without a filter but bought one to protect the front part of the lens when shooting outdoors. Both the K&F and OEM lens caps fit well over the filter. I don't use a filter when I'm shooting indoors. Even outdoors I tend to use one when I'm shooting in dusty environments and only with lenses that don't have a lens hood. It's an extra piece of glass that we put over the lens. It will have some minor imperfections that may be visible when using a pixel peeper. This filter is good, I haven't noticed any degradation in image quality in images I've taken so far. Although I don't use it indoors, I took some pictures to test and didn't notice any difference with or without the filter. The lens cap is OK, but not as good as the OEM cap. The clip is not deep and doesn't provide a good grip. The lens cap holder is a waste. I can't tighten it over the lens barrel so I won't use it. For $10.99, there's nothing to complain about. This is a good filter with a lens cap that protects the lens from dust, scratches, and fingerprints.