Canon EOS-1D X Mark III Advanced User's Manual page 62

Removal
1.
Open the cover.
Set the power switch to <
Check that the access lamp (1) is off, then open the cover.
If [Saving...] is displayed on the screen, close the cover.
2.
Remove the card.
Press the card eject button to eject the card.
Pull the card straight out, then close the cover.
Caution
Do not remove cards immediately after display of a red
shooting or movie recording. Cards may be hot, due to high internal camera
temperature. Set the power switch to <
removing cards. Removing hot cards immediately after shooting may cause you to drop
and damage them. Be careful when removing cards.
>.
> and stop shooting for a while before
62
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