YONGNUO YN560 IV Wireless Flash Speedlite Master + Slave Flash + Built-in Trigger System for Canon Nikon Pentax Olympus Fujifilm Panasonic Digital Cameras

Trouble shooting steps: -User need to do setting on Camera Flash light Control Menu to allow out-put flash light. -Long press button or examine if the battery in right position.

• YN560 IV=YN560III+YN560-TX, Supports Wireless Master Function.
• Supports Wireless Slave Function, fully supports YN560-TX, RF-603 II RF-602 Wireless Transmitter.
• Supports Multiple Trigger Synchronous Mode.
• Supports setting save automatically, custom settings ( fn ).
• Supports ultra-fast charging recycle system, External power supply.