King e-TTL Professional Wireless Flash Trigger with 3 Receivers for Canon DSLR and Flashgun Pixel King E-TTL trigger is a high quality professional E-TTL trigger features a high-sync speed up to 1/8000s. The King wireless flash trigger supports grouping mode and has max of 3 groups. Each group can contain multiple flash units and every flash unit can be set to different power level individually. You can even set the flash power output level via the camera menu if a Canon Canon 580EX II, 430EX II, 320EX, 270EX or Metz AF-48, AF-50, AF-58 flash unit is being used. Cameras support external flash control via menu include Canon EOS 450D, 500D, 550D, 600D, 40D, 50D, 60D, 7D, 5D Mark II, 1D Mark II, 1D Mark IV, 1Ds Mark III.