Samsung GT-S5830I User Manual page 10

To install the SIM or USIM card and battery,
1
If the device is on, press and hold the Power key and
select Power off OK to turn it off.
→
2
Remove the back cover.
Be careful not to damage your fingernails when you
remove the back cover.
10
Assembling
3
Insert the SIM or USIM card with the gold-coloured
contacts facing down.
If you do not insert a SIM or USIM card, you can only
use your device's non-network services and some
menus.