1、Aviation Aluminum Alloy Frame: CNC accuracy machining, anodizing coloring processing, genious design of frame, no need to worry that the filter will scratch or damage the original lens. 2、Multi Layer Coating: High transparency and brightness, restore the true color, and take pictures more wonderfully. Excellent lens grinding process, good physical and chemical properties make the image clearer and make your work more professional. 3、Magnetic Installation: Firm fit, gently close, it can be firmly adsorbed. Equipped with storage box, easy to carry, soft EVA inner support, delicate care. Suitable for ACTION 2 cameras. 4、Reserved Holes: Reserve the holes for the radio and indicator light, which will not affect the radio and indicator light display. Align the two small holes on the filter with the indicator light and the sound pickup hole of the main camera, and gently close to it and absorb it instantly. 5、Reduce Incoming Light: ND filter is mainly used to reduce amount of incoming light when the light is too bright, so that camera can select correct exposure value and avoid overexposure. Block a large amount of scattered light, which can improve the color saturation of picture and make picture more transparent and bright. Using ND filter can also use a slower shutter speed to shoot some special effects, such as foggy water, light trails at night, etc. When shooting videos under the hot sun, can reduce the shutter speed and gate speed, so that the video picture has proper motion blur and looks more comfortable. 4 x Filter1 x Wipe1 x Storage Box1 x Sticker Item Type: Camera Lens FilterWeight: Approx.101g/ 3.6ozMaterial: Aluminum Alloy, Optical GlassProduct Size: 40x40mm / 1.6x 1.6inApplicable Models: for ACTION 2