CANON Speedlite 600EX II-RT flash unit.

Canon Speedlite 600EX II-RT flash unit; Flash unit developed for fast frame rates and optimized for a variety of lighting situations. The "Quick Flash" function enables the Speedlite 600EX II-RT to be triggered before the end of the charging time. The zoom reflector covers a range of 20-200mm, the guide number is 60 (m at ISO 100) and suits most environments. When used externally, the flash can be triggered by radio or optical signal and can control up to 5 groups of flash units at the same time.