The DJI Osmo Action ND Filter Kit includes four neutral density (ND) filters that easily attach to your camera's lens. These filters reduce the amount of light entering the lens, helping you control exposure for more professional-looking shots. Each filter has a ridged exterior that makes it easy to thread onto and off of the lens. The filters are clearly labeled with the ND factor on the ridged edge for easy identification, allowing you to select the right filter for your shooting needs.