DSLR/Mirrorless Full-Frame camera quality glass... in a tiny package.These are spectacular. Unlike another kit I have, you do not need to take off the original lens protection filter: you just pop the filter over the top. So no risk of exposing the actual lens to scratches/dust/oil/etc - not having to keep track of the original piece to reinstall later. I really prefer this approach - it is so quick to just pop a filter on, I find myself using them more frequently than if I needed to sit down and carefully unscrew...The ND filter rotates beautifully - it feels very well engineered/built. Super easy to go from 1 to 5 stops with a little twist. See impact of 5 stops in my sample pics. Functions exactly as you expect: the filter applies light reduction equally across the entire picture: no bright spots, banding, etc.The filters fit perfectly; you do need to take off the original rubber ring (see pic), but this can just go in your pocket until you want to put it back on (I don't think it's really necessary to do so).I find these to be a great value. If you are in the market for fill filters like this, you already know how important they are for your content creation. But, the biggest thing I learned using these filters is 1. They work amazing and the results are impeccable; 2. The "pop on, pop off" design has a huge impact on the likelihood I will use the filter. If you aren't in the same space, with the same lighting and subject for the entirety of your session ... then you are going to need to switch filters. This kit makes that so easy.