The ND 2-4-8 Interchangeable Internal Filter Set is designed to provide users of the Magic Booster P6K Dynamic with an advantage of practicality and professionalism. Advantages of internal ND filters: - avoid lateral light losses - avoid dirt caused by rain and mud - avoid accidental damage such as scratches or chips - light weight, they weigh only a few grams - you can use a filter with all lenses - the particular plugin system is practical and safe.