1.Compatible with: DJI OSMO POCKET 2.CPL filter--- Removes unwanted reflections from non-metallic surfaces such as water or glass and glare from the sun.Increases color saturation,creating deep, rich scenic images.Helps to reduce the amount of light entering the lens. ND filter --- reduces the amount of light coming into the sensor giving you the dom to create your own work by allowing more contbol of the camera's aperture,exposure time and sensor sensitivity settings.The numbers in the back represent the dimming level. 3.Material: Aviation Aluminum Alloy(Frame) + Optical Glass(Lens) 4.Strong magnetic adsorption stable mounting(you can shake,wag or jump at will during following shot or sports film,and don't need worry it'd fall down). Rapid Replacement(you can mount,dismount or replace the filters in a split second.change the filters depending on different scenes and you won't miss the wonderful shots). NO Damage(the ingenious frame structure design makes it possible to isolate the filter from the original lens,meanwhile provide good protection.)