Canon Speedlite 600EX II-RT Flash light- barely used

Description

The Canon Speedlite 600EX-RT is a high-output, multi-feature flash unit for Canon EOS cameras, compatible with E-TTL II, E-TTL and TTL autoflash and external flash metering systems. The Speedlite can be used as an on-camera flash that attaches to the hot shoe of the camera (normal shooting) and as a master unit or slave unit during wireless shooting. In addition to these three functions, the Speedlite also has dust and water resistance equivalent to EOS-1D series cameras.
Note that the 600EX-RT is equipped with a wireless flash shooting function that uses either radio transmission or optical transmission. The 600EX is equipped with a wireless flash shooting function that uses optical transmission only.