(Yongnuo YN600EX RT II Speedlite Flash / Flashgun, Only for Canon EOS DSLR's with superb specs and performance. Flashgun - Supplied with a) One YN600EX-RT II can be used as master unit to trigger another YONGNUO YN600EX-RT or Canon's 600EX-RT, and live display the flash groupings of slave unit and recycling information.
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