The Graduated Neutral Density Kit plus includes: • graduated ND2 hard (1 F-stop) • graduated ND4 hard (2 F-stops) • graduated ND8 soft (3 F-stops) • Cokin filter holder (adapter ring sold separately) • 3 filter cases graduated Neutral Density (ND) filters allow you to reduce the amount of light reaching the sensor on a portion of your picture. This helps control the exposure difference between highlights and shadows for a more balanced exposure and dramatic effect. By rotating the filter-holder and adjusting the position of the filter up and down you can precisely control where the filter has an effect on the image.