Guide Number: GN60 (ISO100, 200mm). 【Built-in 2.4G Wireless Trigger System】Can work as a master or a slave unit, and fully compatible with RF radio triggering signals from other ' speedlite. 【Optical Wireless Slave Function】The YN690EX-RT supports receiving wireless signals from or flash lights as the main signal, supporting S1 and S2 flash modes, allowing you to integrate it seamlessly into your existing flash setup.
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