Haida filters for the 75 mm system. 75 x 100 mm format with NanoPro technology. The new NanoPro series outperforms all known filters to date. NanoPro filters offer a whole range of advantages: they are highly scratch resistant. - Virtually zero dominant - dirt does not stick. The filters are made of K9 glass with multi-layer NanoPro coating and bevelled edges. The coating produces a visually tinted feel, but it is not transmitted to the image. Bevelled edges allow easy insertion into the filter holder. They are compatible with Lee and Benro, among others.