UV filters something many photographer takes for granted or think will affect their images when out in the field,I had previously purchased the K&N Adjustable ND filter that does away with the cross effect you normally get and I was so impressed I thought I would try out one of their UV filters to see how well it holds up to some of my others, first thing you will notice is that it is very slim "ultra Slim" Double threaded yet only 3mm in depth impressive indeed.you will also notice right away that it has some coating on the glass which blocks and prevents the harmful effects of UV rays and eliminates haze that can register a bluish cast from scenic shots.One if the most important features for me was to see if the claim that it does not affect image quality was true as many other filters have some slight effect on sharpness, and to do this I got the back of the box from the uv filter which has a high contrast of black and white and also had a light opposite and one to the right to test for glare effects, The result which I have posted down below, which was extremely impressive, I zoomed in at 100% and could not see any major effects to my image quality, least to say that with my own eyes I could not see any negative effect to the quality.I will let the photos speak for themselves.you will hear a lot of people say UV filters are pointless and maybe so with lower quality ones but I have had a uv filter save my 16-35mm lens when it fell, I also use them for my fitness shoots which I shot in a warehouse with loads of dust and when I use smoke grenades this prevents small particles entering the lens as well as settling on my elements.this filter also has notches to make it easier to unscrew, i know this is a nice welcome for me as i have to carry a flat balloon with me in my bag to help grip some of my others when they get stuck.below you will see two other filters which i have stacked next to the K&F concept these are also meant to be slim line, you will be able to see the difference in thickness and quality.Last but no means least the last two images are the before and after the filter was attached to prove that image quality is not effected.For £7 you have nothing to lose and lots to gain trust me :)