Yongnuo YN560 IV 2.4G Wireless Flash Speedlite for Canon Nikon Olympus Sony Pentax 1.YONGNUO YN-560IV flash speedlite is yn560III upgraded version,a Combination of YN-560 III and YN560-TX all functions. 2.Supports Wireless Slave Function, fully supports YN560-TX, RF-603 II RF-602 Wireless Transmitter. 3.Supports ultra-fast charging recycle system, External power supply. 4.Supports setting save automatically, custom settings ( fn ).It has built-in wireless trigger system, it can be a flash speedlite, but also a flash controller Transmitter. 5.if your camera is sony,and not built a standard hotshoe,you may need to purchase a hotshoe adapter separately.