Speedlite 600EX II-RT The Speedlite 600EX II-RT is engineered for fast frame-rate shooting, and performs in the most demanding situations. off-camera or in the hotshoe, its versatility allows you to take complete control over lighting. Benefits Shoot faster and for longer Reliable performance on- and off-camera Creative off-camera lighting from any direction using radio wireless control Powerful performance, with guide number 60 (m, ISO100) Easy to use, with intuitive controls and an information display