Yongnuo YN622N YN622N YN622N Wireless TTL Flash Trigger for Nikon Camerad Using digital FSK 2.4 Ghz frequency band with 7 channels, it has three modes, I-TTL, manual and multi and it can fire flashes at 360 degree direction It supports FEC, FEB, FEL, high-speed sync, 1st: curtain, 2nd: curtain, modeling flash, I-TTL group ratio (All/A:B/A:B C) Support full I-TTL pass-through function when on camera