LG T-Mobile C1200 User Manual page 20

Position the lugs on the bottom of the battery into the retaining
holder. Then, push the top half of the battery into position until the
latch clicks.
Only use the mains adapter supplied with your phone.
With the battery in position on the phone, connect the lead from
the travel adapter to the bottom of the phone. Make sure that the
arrow on the lead connector is facing towards the front of the
phone.
Connect the other end of the adapter to the power outlet.
Use of unauthorised accessories could damage your phone
and invalidate your warranty.
Do not force the connector as this may damage the phone
and/or the mains adapter.
C1200 User Guide