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NEEWER FT-16 16 Channel Wireless Power-Control Trigger (Transmitter Receiver Set) for Canon

The wireless power control flash trigger FT-16 is designed for versatile use
The trigger set consists of a transmitter on camera and a receiver on-flash
Remote control lamp and focus lamp and a buzzer switch
Easy to install and use the camera control in hot shoe on demand
Set power ratios of up to 16 groups of remote flashes