Panasonic KX-TC1871ALB Operating Instructions Manual page 87

Connecting the optional headset to the handset
Open the headset jack cover, and connect the headset to the headset
jack as shown below.
When the optional headset is connected to the handset, make sure
to use the headset to talk with the caller. If you want to have a
normal cordless phone conversation, disconnect the headset.
How to wear the headset
1 Place the headset on your
head and attach the clothing
clip to the desired position.
Headset Jack
2 Adjust the microphone to
a comfortable position.
≥Place the microphone near
your mouth.
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