This accessory sends flash instructions to a speedlight located far away. When you want to use speedlights wirelessly or when you want to fire multiple flashes, it is convenient because you can change settings for multiple speedlights with one unit. With wireless multi-flash photography using Speedlight 600EX-RT*, 580EX II, 430EX II, 320EX, and 270EX II, you can control 580EX II, 430EX II, 320EX, and 270EX II that are set as slaves. *600EX-RT cannot be controlled via radio communication. Compatible cameras ALL (excluding EOS M100, EOS M10) *EOS M series requires off-camera shoe cord OC-E3, which is sold separately, depending on the lens.
