Item Type: ND Filter_x000D_ Material: Optical Glass+Alloy_x000D_ Color: Black_x000D_ Weight: Approx. 27.0g/1.0oz_x000D_ Fit for Osmo Action camera_x000D_ _x000D_ Effect: Reduce the amount of light entering and extend the exposure time 1Reduce the amount of light entering the camera, extend the exposure time, and effectively reduce the shutter speed. 2The number behind ND represents the ability of the ND lens to block light, the larger the number, the strong the light reduction ability. 3Made of high?definition clear colorless optical glass, which helps to improve photo clarity and color reproduction, fit for Osmo Action camera. 4Protect the lens from dust and scratches, in normal use, it can be shaken, or jumped at will without worrying about falling off. 5Strong magnetic adsorption design, can be firmly adsorbed by lightly approaching, perfectly fits the lens, well coordinated, easy to disassemble.1 x NDFilter 1 x Manual