Canon EOS-1D X Mark III DSLR Camera (Body Only) - Manual (Page 539)

2.
Select [Send selected].
3.
Select images to send.
Turn the < > dial to select images to send, then press < >.
To switch to three-image display for image selection, press the < >
button and turn the < > dial counterclockwise. To return to the
single-image display, press the < > button.
After selecting the images to send, press the < > button.
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