Samsung SGH-t309 - Manual (Page 11)

Section 1: Getting Started 7
Activating Your Phone
Section 1
Note: When you need to remove the SIM card, slide it, as shown, and take
it out of the socket.
4. Place the battery so that the tabs on the end align with
the slots at the bottom of the phone (1). Press the battery
down until it clicks into place (2).