This Cokin A Series Adapter Ring allows you to attach the Cokin Filter Holder to a lens with a filter diameter of 55mm. The "A Series" filters are recommended for use on lenses with a filter diameter between 36mm and 62mm, which have a focal length of more than 35mm.
You can even slide three filters into the filter holder at once to create unique effects. The front slot is suitable for a round filter, such as a polarising filter. In the other two slots you can slide square filters. You also decide where in the photo a filter will have an effect. In short: you have unlimited creativity at your disposal!