The NiSi V7 ALPHA is designed to use 100mm wide filters that are 2mm thick and can support 3 filters 100mm wide that are 2mm thick. Included is an 82mm adaptor ring to allow the holder to connect to any lens with an 82mm standard filter thread. The holder can be combined with our V7 adaptor rings to allow the use of sizes from 49mm to 77mm (Sold separately). The three 100x100mm IR ND filters included in the kit uniformly reduce the amount of light entering the lens by 3, 6, and 10 stops. ND Filters can enable greater motion blurring and image detail by allowing a large aperture and a slow shutter speed.