Model: YN560 IV. S1 and S2 light are sensitive trigger, S2 with pre-flash-canceled mode. Wireless triggering distance: 100m(2.4G wireless); 20-25m indoor, 10-15m outdoor. 【Sound Prompt Function】When the sound prompt system is enabled, different sound modes will prompt different working conditions of the so as to allow you to focus on shooting process (Note: the sound can be turned off).
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