The HOYA PRO-ND filter kit is an essential kit for both photo and video. It includes 3 screw-on filters of neutral density: ND8 filter with a density of 3 diaphs, very useful in video to use the full aperture during daylight as well as in photo to capture the movement of fast-moving subjects at night (cars, fireworks, etc.) • ND64 filter with a density of 6 fps, ND1000 filter, these 2 filters (ND64 and ND1000) allow for long posing to capture the movement in your images, smooth the movements of water. The PRO-ND HOYA filters are made from high-quality optical mineral glass with the multi-coated Accu-ND coating ensures excellent colour neutrality. These qualities make it possible to combine 2 or 3 filters together to have 7 density combinations in total: • ND8 = 3 diaphs • ND64 = 6 diaphs • ND8 + ND64 = ND512 = 9 diaphs • ND1000 = 10 diaphs • ND8 + ND1000 = ND8000 = 13 diaphs • ND64 + ND1000 = ND64 = ND64 = ND1000 = ND1000 = ND64 = ND1000 = ND64. 000 = 16 diaphs • ND8 + ND64 + ND1000 = ND512000 = 19 diaphs. Please note that the very important extension of the application time may result in chromatic drift depending on the camera models, despite the qualities of the filter. The filter overlay can also result in vignetting depending on the focal length. Test should be carried out first.