KIT INCLUDES: (1)ND4 Filter; (1)ND8 Filter; (1)ND16 Filter; (1)ND32 Filter; (1)Package Box. GREAT FUNCTION: ND filters reduce the amount of light reaching the film without affecting the color, allowing you better control over camera aperture, exposure time and sensor sensitivity settings. It can produce a lower depth of field or achieve a sharper photo Multi-coated optical glass: made of optical glass, good transmittance, crystal clear glass for high definition video; It is water, oil resistant and scratch resistant, reduces fingerprint stains. It also ensures a low refractive index / excellent colour neutrality / perfect target transmission. Quick Installation Unscrew the original filters counterclockwise. Then turn the filter clockwise to allow quick replacement between filters Quality Design The filter frame is made of high quality aviation aluminum frame, which is lightweight and durable. The lens function is not affected. The ND filter is made of high quality optical glass, which can withstand scratches and protect your camera lens well Note: Lens 、CPL &ND/PL Filter though the filter features a waterproof coating, the entire action camera cannot be used underwater