【GN66】 GN66@ ISO100，199mm High guide number 2.4G wireless speedlite, supports M/Multi/-- mode. 【Master control】Supports wireless master control function, realize six groups of light control YN660 can be used as master control unit, be equipped with six groups of independent grouping control ability, realize remote control the flash mode, output and focal length of YN660、YN560 IV、YN560III. 【Off camera】 Supports wireless slave function, fully supports the YN660、YN560 IV、YN560-TX、RF605、RF603（II）、RF602 wireless transmitter One YN660 can respectively accept the signal transmitted from the YN660、YN560 IV、YN560-TX、RF605、RF603 (II)、RF602 wireless transmitter, with 16 channels for option; when the YN660、YN560 IV and YN560-TX used as transmitter, it can realize remote flash parameter adjustment. 【Trigger】Multiple flexible trigger synchronous ways YN660 can be triggered through the camera, 2.4G wireless triggering, S1 and S2 pre flash trigger avoidance. 【Custom】Supports automatically save settings and custom settings Fn The parameters on the flash will automatically save when the flash turned off; the users can customize setting the flash function as needed. 【Sound】 Special sound prompt system Turn on the sound prompt function, the speedlite will prompt the working state, allows you to focus on the creative process (note:the sound prompt can be turned off). 【Zoom】Supports electric zooming function Through short press the 【ZOOM】button and rotate【Select Dial】, the flash coverage can be changed between 24~199mm with cyclical variation. (note:199mm is equivalent to 200mm focal length). Ultra fast Charging Recycle System, supporting External Power Supply Equipped with Big Size LCD Display Screen, standard PC Synchronous Interface | 
