Features: It transmits all the settings in External Flash Menu of your camera to remote flash (es), you can control flash (es) through camera menu. It supports TTL function.LCD screen display, multi-buttons quick operation. The firmware can be upgraded through the USB (Universal Serial Bus) interface. Support wireless shutter release function. The focal length (zoom)of the A/B/C three groups of flash can be adjusted separately. Equipped with the AF focus assist light (can be disabled). Grouping flash mode: E-TTL/ Manual flash/ Super sync. Supporting mixed use of the A/B/C three groups of flashes with E-TTL, Manual flash, or Super sync flash mode. The exposure compensation or flash output of A/B/C three groups of flashes can be adjusted separately. Shutter Sync: first curtain sync, second curtain sync & FP high-speed sync, the highest sync speed is 1/8000s. Support exposure compensation, flash value lock function (FVL). Support simulate (modeling) flash, red-eye reduction flash. Support the flash zooming (auto). Super Sync (SS) time delay adjustment, for higher x-sync speed than the camera allows. Settings saved automatically. The flash sync signal can be input through the PC port. Support the basic flash trigger (max sync speed is 1/250s) of standard hot shoe (non Nikon body). Compatible Camera list:A: The EOS DSLR camera with external flash control menu: Canon 5D Mark II, 5D Mark III, 1 Ds Mark III, 1D Mark IV, 1D Mark III, 7D 60D 50D 40D 450D 500D 550D 600D 650D 1000D 1100D.B: The EOS DSLR Camera without external flash control manual: Canon 5D 10D 20D 30D 300D 350D 1D 1D Mark II. Compatible Flash: Compatible ETTL Flash: (It suport wireless remote control through camera menu ). Canon 600EX (RT ), 580EX II, 430EX II, 320EX, 270EX IIYongnuo YN-565EX C, YN-468 II C, YN-467 II C, YN-465 C (Yongnuo flash units dont support HSS Function). Note: 430EX & 580EX or other parts of flash is not supported remote control via the camera menu, you need to manually set the flash parameters. The compatible shutter cable list:C1-60D / 70D / 400D Series / 500D series / 600D Series / 1000D Series C3-40D / 50D / 7D / 1D Series / 5D series