Andoer Oloong SP-780 i-TTL GN50 Flash Light Lamp Automatic Manual Zoom Electronic Wireless Speedlite Speedlight Master Slave for Nikon D5 D4S D750 D7200 D7100 D610 D5500 D5300 DSLR Camera With a high guide number of GN50. (ISO100, 180mm) Support multiple flash modes, including i-TTL/ M. Support 22 levels flash output control (1/ 1 to 1/128) in M mode. Can be used as on-camera master unit or remote slave unit to form a flash group. Support 2 different slave modes: F1(nonsupport TTL)/ F2 (support TTL).