The K+F Concept Slim 52mm Variable Fader is a great item for several reasons, but its main function is to remove shadows/reflections from water and other non-metallic objects. I was really impressed with its functionality and how well it fastens, and I was equally impressed with its design and ease of use. Like other filters, this one is threaded and you can easily twist it to adjust it to your needs. The filter is also stackable so you can place additional filters or a cap on top, great for additional effects and preventing scratches. Speaking of scratches, using filters also helps protect your lens. So using filters not only creates a beautiful effect, but can also prevent random items from coming into contact with what would normally be an expensive item. I would also like to point out the packaging and commend the company for creating something that will keep your item safe using both hard plastic and soft foam. This is probably the best packaging with filter I have ever seen and it really made me happy to see it. Please note that this was supplied for trial purposes and was used multiple times prior to review. As with any filter, you should experiment with it before taking the shots you want to make sure you have it dialed in perfectly. This was a lesson I learned some time ago, and unfortunately the learning curve was steep.