Sony SGPT21 - Manual (Page 35)

To insert a microSD memory card
1. Open the bottom cover and remove the battery pack.
2. Locate the microSD memory card slot.
3. Hold the microSD memory card with the contacts facing down and the arrow pointing toward the microSD
memory card slot.
4. Carefully slide the microSD memory card into the slot until it clicks into place.
Note
Be careful not to insert a microSD memory card at the wrong orientation. If you force it into the slot upside
down, the slot may be damaged. For details, refer to the manual of the microSD memory card.