used this UV filter from K&F Concept, Nano-X series, to protect my favorite 50-1.8 fixed lens. Unlike other proven models, this one is really super transparent and really very light, so much so that when you look at it from the front, it almost seems like there is no lens. It is very well made and I really liked that it also comes with a cap of the same diameter and the wrist strap so as not to lose the cap when taking pictures. It also comes with a small vacuum-packed microfiber cloth: I kept it closed and ready, for the first time I have to clean the lenses to always have a clean cloth on hand. The structure that holds the lens is made of thin metal painted black. The filter data is displayed on the side and the screw is perfectly screwed onto the lens head. It is sold in different sizes, so make sure you choose the right size for your lens. Being standard thread, these filters can be used on any camera lens, as long as the lens has the right diameter. When taking pictures, this filter is really perfect: in practice it is unnoticeable and at the same time it protects the lens from dust and scratches. Really good product, which is advertised with bravura for its excellent overall quality and the fact that it is practically invisible in the photos, without creating strange reflections or light effects.