HTC U11 User Manual page 29

Note: If you purchased an optional microSD card, place the microsSD card to the SD holder of the tray.
For details, see Insert SD
5. When reinserting the tray, make sure it is facing up so that your cards don't fall out. Hold the tray
with the outer card holder between your fingers, and then steadily slide the tray all the way into
the slot.
Set Up Your Phone
Card.
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