YONGNUO TTL Flash Unit Speedlite YN568EX YN-568EX with High Speed Sync 1/8000 for Nikon Digital Camera Support HSS (the High Speed Sync) up to 1/8000 second TTL Flash With GN58@ ISO100, 105mm Supports for Nikon's System and Supports Auto/Manual Zooming Comprehensively Support TTL Functions and Sound Prompting System Advanced Settings On Flash and Automatic Setting Saving