Unique Fine Macro mode Revolutionary Fine Macro technology stabilizes the precise fine light control from 1/128 to 1/1024 in 1/6 Ev steps fine turning to achieve the accuracy of microscope. While in Manual mode, the power ratio can be adjusted from full power to 1/64 in 1/3 Ev steps. This mode helps to achieve more stable quality when shooting high sensitive images. Tube flash design Tube flash design is applied to achieve uniform light effect. Light power ratio control can be adjusted independently according to the light conditions. Expansion flash head The ring head can adapt the lens from 49 to 82mm. Expanding the ring head to eliminate the problem of vignetting and hidden corners during macro photography. Package includes adaptor rings 52, 58, 62, 67, 72 and 77mm (49, 55 and 82mm are optional for purchase). Wireless TTL Wireless TTL with multi-function remote control system. MF18 can be used as master flash to control slave group A and C* with ± 3.0Ev compensation setting. Perfectly assorts with Di866 Mark II / Di622 Mark II or Original Canon/Nikon flashes to create more lighting effects.