Tadiran Telecom FlexSet 280 User Manual page 56

Display Message Key LED
Privacy during a call: activate/cancel
While on a call you can speak privately without other parties joining in. This is
done by using the Privacy key. The Privacy key turns the feature on and off and
can be pressed as many times as necessary. Once Privacy is defined for your
station (all calls) the key LED remains illuminated, even if the key is pressed to
temporarily override the Privacy feature. However, when your call is
completed the telephone returns to the permanent status, private or non-private,
as previously defined for all calls.

Note: The Exclusive Hold key operates in the same manner as Privacy,
except that the messages are relevant for Exclusive Hold.
Boss Group: Using 31 FlexSet 120/280 User Guide