The Corded Trimline Phone from AT&T features Caller ID, 13-number memory, flash, redial and mute. Plus, the TR1909W is user friendly with a light up keypad and a desk or wall mountable design. NOTE:* This units does not need AC power for a dial tone. However, it requires batteries to operate the Caller ID. * To wall mount the customer should refer to the owner's manual for instructions. It requires the bracket to be rotated 180 degrees when wall mounting the phone.