Canon Speedlite 600EX II-RT with Deluxe Accessory Bundle and Starter Kit This revision improves continuous flash performance by up to 2.0x The two-way 2.4 GHz radio system provides added reliability and a range up to 98.4' among up to 5 groups with a total of 15 individual Speedlites. Features a guide number of 197 ft. (60m) at ISO 100 to help achieve the desired lighting For optimal performance in any situation, the Speedlite 600EX II-RT includes the SBA-E3 Bounce Adapter and SCF-E3 Color Filter for 600EX II-RT Bundle includes a universal remote, heavy duty off-camera flash cords, pro video grip, universal diffuser, bounce adapter, color filter, 4AA Batteries, and a speedlite case