Canon Speedlite 600EX II-RT Series: Speedlite Specifications: Number of Flashes: Approx. 100–700 flashes. Compatibility: Type-A EOS cameras (E-TTL II / E-TTL autoflash) Type-B EOS cameras (TTL autoflash) Guide Number: Approximately 49.2 ft. at ISO 100. Maximum Guide No. is approximately 196.9 ft. at ISO 100 and 200mm flash coverage. When the extendable wide panel is pulled out, the flash coverage is 14mm. AF-assist Beam: System: Infrared AF-assist beam Compatible AF System: TTL second image formation phase-difference AF Supporting 1 - 65 AF points (28 mm or longer focal length) Phase-difference AF during viewfinder shooting Quick mode during Live View shooting or movie shooting Effective Range (Approx.): At center: 2.00 - 32.8 ft. At periphery: 2.00 - 16.4 ft. Recycling Time: Normal flash: 0.1 - 5.5 sec. Quick flash: 0.1 - 3.3 ...