YONGNUO YN685 GN60 2.4G System ETTL HSS Wireless Flash Speedlite with Radio Slave for Canon YN685 has the two built-in Wireless Trigger systems, YN-622C system and RF-603 sytem Which can receive the wireless trigger singnal from YN-622C,YN-622C-TX, YN-560 IV, YN560-TX, RF-603 II, RF-605 Which can trigger more than two off camera flashs in manual mode, TTL mode, multi mode, and even remtoe control the each group' flash in flash mode, flash output, focal length and focal length synchronization GN60@ISO100, 200m --- 2.4G wireless speedlite of high guide number High-speed Sync, Second-curtain Sync, Flash Exposure Compensation, Exposure Bracketing ( FEB ), FE Lock