Clarity C4220 User Manual page 9

TALK: To make a call Press the TALK button or predial
number and press Talk.
Volume Control: The dial controls the volume levels
of the handset, headset or neck loop and ringer volumes.
Boost: When pressed, an extra level of amplification
is added over the entire range of volume.
Speaker: Press the Speaker button to activate the
handset speakerphone. Press again to switch back
to earpiece.
C4220 Handset
Features