The K+F Concept 52mm slim Variable Fader is a great item to have for a few reasons, but its primary function is to remove shadowing/reflections off of water and other non-metallic objects. I was really impressed with its functionality and just how well it attached, and I was equally impressed by the design and easily it could be used. Like other filters, this threads on, and you can easily turn to adjust it to meet your needs. The filter is also stackable, so you can place other filters or a cap on top of it, which is great for added effects and for preventing scratches. Speaking of scratches, using filters also helps with keeping your lens safe, so using this not only adds a nice effect but can also keep random items from contact what is normally a high-priced item.I wanted to note the packaging as well and give props to the company because they created something that keeps your item safe with both hard plastic AND soft foam. This is probably the best packaging I have EVER seen with a filter and it made me really happy to see it.Please note this was supplied for sampling purposes and has been used multiple times before reviewing. As with any filter, play with it before going for your desired shots to make sure you have it down perfectly; that was a lesson I learned a while back and the learning curve was sadly steep.