1. It shades the lens from stray light, improving your contrast and image quality.
2. It can assist in keeping moisture or wind-blown debris off the lens.
3. Made of metal and with hollow-out design, nice and practical.
4. Convenience to carry for outdoor photographing.
5. Lock on to the lens directly with a screw-in type.
6. Prevent unwanted light or glare entering your lens when taking pictures. Give your pictures better contrast and better picture quality.
7. The filter adapter ring was custom designed for FUJIFILM X100 camera to accept any 49mm threaded filter.