Canon EOS-1 D X Mark II Instruction Manual page 481

Button Operation for the Quick Control and
Custom Quick Control Screens
When you press the <W>, <o>, <Q>, <S>, <i>,
<O>, or <B> button, the setting screen will appear and you can use
<6>, <5>, <9>, and <B> to set the function.
Shooting mode
Metering mode/
Flash exposure compensation
ISO speed
White balance
B Button Functions
AF operation / Drive mode
AF point selection
Exposure compensation
AEB
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