DESC: With a RadioShack Caller ID System and Caller ID service from your phone company, you can know a caller's name and number before you answer. When the phone rings, caller information appears on the screen. Plug the System-1752 stores information for 99 calls, so you'll know who called while you were out. With one-button callback, you can return a call to any local number displayed on the screen. Indicator alerts you to new calls.