Support ITTL auto flash, manual flash, multi stroboscopic flash, 1/8000s high-speed sync, first curtain sync, and second curtain sync, etc.2.4GHz Frequency, 25m effective trigger; Enable to use as Master flash and Slave flash. 4 independent transmission channels, 3 groups (A,B,C) AF-assist Beam- When autofocus can not achieve focus on the subject in low-light or when contrast is low, the built-in AF-assist beam will actives automatically to help autofocus. Flash Coverage 24-105mm; Power range from 1/1 to 1/128 power; 5600k±200K color temperature. Automatic power off function; USB port for firmware upgrades. Powered by 4 * AA batteries.(Batteries are not included.) Show More Show Less
