For my Panasonic Lumix G lenses, I needed two "protective filters" so that rain and fingerprints can't damage the front lenses. There are different opinions on the net about the effect of UV filters, so I don't want to say anything more about it, but there is a blue-tinted coating on the K&F Concept Pro UV filter, the delivery condition is perfect and the packaging is (especially in view of the the price) can almost be described as luxurious. A first check does not reveal any adverse effects on the image quality, and the slim design means there are no shadows on the 12mm lens. Lens caps continue to fit securely, and the lens hood also fits the lens either way. I see the handy "teeth" on the outer edge of the frame as a big advantage - finally someone has thought along! Especially with the "slim" filters, it is sometimes rather tedious to get them off again after they have been screwed "safely". There are even tools that make this removal possible in the first place. But that's a thing of the past here, with this practical ribbing on the edge it's no longer a problem. At that price you can also have one or two of these filters with you in your camera bag and when the mud has splashed you can quickly put a clean one on - just perfect!