Canon Speedlite 430EXIII-RT Instruction Manual page 91

' Device equipped with radio transmission wireless master
function
600EX-RT and ST-E3-RT
( Speedlite equipped with radio transmission wireless slave
function
600EX-RT
) Device equipped with optical transmission wireless master
function
600EX-RT, 600EX, 580EX II, 580EX, 550EX, 90EX, MT-24EX, MR-
14EX II, MR-14EX, ST-E2, and EOS DIGITAL cameras with optical
transmission wireless master function by built-in flash
* Speedlite equipped with optical transmission wireless slave
function
600EX-RT, 600EX, 580EX II, 580EX, 550EX, 430EX II, 430EX,
420EX, 320EX, 270EX II
+ Off-Camera Shoe Cord OC-E3
Enables the 430EX III-RT/430EX III to be connected to the camera
up to approx. 60 cm / 2 ft. away.
When using a Speedlite without a function for switching the firing groups (A,
B, C) in *, you can use the Speedlite as a slave in firing group A during
wireless flash shooting (you cannot use it as a slave in firing group B or C).
430EX III-RT/430EX III System
91