Samsung Focus S SGH-I937 User Manual page 11

Replace the battery cover (the back of the phone) by
3.
putting the tabs into the slots as shown by the arrow (1).
Press the cover down (2) into place.
4.
Press down firmly along the edges of the cover to ensure
5.
that the cover is flush with the phone (3). You should hear a
light click as the cover locks in place.
Note: Make sure the battery is properly installed before switching on the
phone.
Getting Started 6