Nokia N75 - Manual (Page 6)

Memory card
You can use a compatible microSD card as extra storage space to save the
memory on your device. You can also back up information from your device
to the memory card.
Insert the memory card
1 To insert the memory card, place your finger in the recess
of the door of the memory card slot, and open the door.
2 Insert the memory card in the slot. Make sure that the
contact area on the card is facing down and towards the
slot with the bevelled corner facing the base of the
device. Push the card in. You can hear a click when the
card locks into place.