Canon EOS-1D X Mark III DSLR Camera (Body Only) - Manual (Page 709)

Reference
Changing the Camera Nickname
Virtual Keyboard Operations
Configuring IPv6
Changing the Camera Nickname
You can change the nickname of this camera (displayed on connected devices) as desired.
1.
Select [ : Nickname].
2.
Enter text using the virtual keyboard .
When you finish entering characters, press the < > button.
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