bought this lens filter because I was looking for a filter no thicker than 3mm that would fit in a new Haoge lens hood (which cannot take thick filters) for my X100V to protect the lens and the camera to make weatherproof. If you don't know anything about the new X100V, you need a filter that is weatherproof. After some searching for a 3mm thick filter I found this filter from K&F Concepts on Amazon. I was skeptical that it would only cost £5.99 and there have been some complaints of a color cast. However, I thought I'd give it up for the price. The box it arrived in isn't the best, but it did its job and the filter arrived unmarked. I held it over a white surface and I could actually see a slight shade of brown. However, I don't see any color cast in the pictures. If you hold the filter up to the light you can see a purple reflection. I have tried to show this in the pictures but there is some fading. It looks very similar to the anti-reflective coating you have on glasses - I don't mind that. Overall I'm amazed, it's actually a really good filter with good spread and no obvious ghosting — I shot in the sun yesterday and it worked really well. I've bought far more expensive filters in the past that weren't as good. Recommended — consider buying a second one as a spare!