AT&T CL84367 Complete User's Manual page 23

Getting started
Installation options
4. Slide the handset tab upward. Rotate the handset tab by 180 degrees.
5. Make sure the telephone line cord and power adapter cord are securely
plugged into their jacks on the back of the telephone base. Plug the power
adapter and telephone line into the wall outlets.
Handset tab
Switch hook
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