Complete with built‎-in radio transmission wireless functionality‎,‎ the Speedlite 600EX II‎-RT sits at the top of Canon‎'‎s on‎-camera E‎-TTL / E‎-TTL II compatible flash lineup with a powerful guide number of 197‎'‎ at ISO 100 and 200mm‎.‎ This revision improves continuous flash performance by 1.1‎-1.5x‎,‎ or up to 2.0x with optional battery pack‎,‎ simplifies the menu system for faster operation‎,‎ and includes a specially designed bounce adapter‎,‎ a hard color filter‎,‎ and an updated soft case‎.‎ 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.‎ This system also does not need direct line‎-of‎-site like traditional optical‎-based transmission and will work through obstacles‎.‎

For added coverage and functionality‎,‎ the flash‎'‎s zoom head can reach from 20‎-200mm‎,‎ with the option for wide 14mm coverage when the built‎-in diffusion panel is used‎.‎ Also‎,‎ the unit can tilt from ‎-7 to +90° and rotate 180° either left or right for complete bounce capabilities‎.‎ On the back of the 600EX II‎-RT is a backlit dot‎-matrix LCD panel that displays the status and allows users to easily access and change settings‎.‎ Additionally‎,‎ the flash is durable with a redesigned contact construction and improved dust and water resistant sealing‎.‎

Other capabilities of the 600EX II‎-RT include a stroboscopic mode as well as high‎-speed‎,‎ first and second curtain sync settings for more control over your image‎'‎s final look‎.‎ The flash is powered by 4 AA batteries and has a port for an optional external power pack‎.‎ The rated recycle time is 0.1‎-5.5 seconds‎,‎ but can be sped up to 0.1‎-3.3 seconds in Quick Flash mode‎.‎ It comes with a bounce adapter‎,‎ a hard CTO filter set‎,‎ a mini stand‎,‎ and an updated soft case that holds the flash and accessories‎.‎

• AF assist beam works with up to 61‎-point High Density Reticular AF system
• There are 15 custom functions and 6 personal functions for maximum customization
• Optical transmission is available in addition to radio transmission
• Quick Flash settings speeds up recycle time and flash duration
• Manual power settings from 1/1 to 1/128 power in 1/3‎-stop increments
• Flash color temperature information is automatically transmitted to the camera
• Automatic power off function
• Flash exposure compensation from ‎-3 to +3 EV in 1/2 or 1/3 EV steps
• PC sync port and remote release terminal for off‎-camera triggering
• Flash duration of 1.8 ms or less‎,‎ or 2.3 ms or less in Quick Flash mode
• Stroboscopic setting from 1‎-500 Hz‎,‎ or 1‎-199 Hz during optical transmission wireless shooting
• Wireless flash ratio control from 1‎:‎8 to 1‎:‎1 to 8‎:‎1 in ½‎-stop increments
• Compatible with ST‎-E3 Speedlite Transmitter
• Approximately 100‎-700 flashes with AA alkaline batteries
• Locking metal foot
• Bracket mounting hole
• Built‎-in retractable bounce card